Contenido de duramen y de albura en Eucalyptus globulus y Acacia melanoxylon implantadas en Argentina

Los objetivos del trabajo fueron determinar la proporción de duramen y el ancho de la albura en Eucalyptus globulus y Acacia melanoxylon, estudiar su variación axial en el fuste y establecer re-laciones entre duramen y el diámetro y volumen del fuste. Se muestrearon 10 árboles de E. globulus de 9 años y 10 árboles de A. melanoxylon de 19 a 32 años, en dos sitios de Buenos Aires, Argentina. En cuatro rodajas por árbol (base, 1.3 m, 30 % y 50 % de la altura total), se determinaron el área, volumen y porcentaje de duramen y el ancho de albura. En E. globulus el porcentaje de duramen dis-minuyó significativamente hacia el ápice (46 % en la base y 30 % en la última altura muestreada); en A. melanoxylon no hubo diferencias significativas (48 % a 31 %). El ancho de albura fue relativamente constante a lo largo del fuste, siendo en promedio de 26 mm para ambas especies. El volumen de du-ramen con respecto al volumen del fuste fue de 37 % para E. globulus y de 43 % para A. melanoxylon. Se hallaron regresiones lineales significativas entre el volumen del duramen y dos variables de interés comercial e inventarial: volumen  del fuste y diámetro a la altura de pecho. AbstractThe aims of the work were to determine heartwood and sapwood content in Eucalyptus globulus and Acacia melanoxylon trees, to study their variation and to establish relationships between heart-wood and log volume and diameter. Ten trees of 9-years old E. globulus and ten trees of A. melano-xylon between 19 and 32 years old were sampled in Buenos Aires, Argentina. Heartwood area, vo-lumes and percentage, and sapwood width were measured and calculated at four discs by tree (base, 1.3 m, 30% and 50% of total height).  E. globulus heartwood percentage decreased significantly from the base upwards (46% at the base and 30% at the last sample height); in A. melanoxylon axial diff e-rences were not significant (48% to 31%). Sapwood width was relatively constant with sample height and its means were 26 mm for both species. Average heartwood volume represented 37 % of the log volume for E. globulus and 43 % for A. melanoxylon. For both species, linear regression models show positives relationships between heartwood volume and two variables of commercial and inventorial importance:  log volume and diameter at breast height

Soil nitrous oxide emissions from grassland: potential inhibitor effect of hippuric acid

In grassland systems, cattle and sheep urine patches are recognized as nitrous oxide (N2O) emission hot spots due to the high urinary nitrogen (N) concentrations. Hippuric acid (HA) is one of the constituents of ruminant urine that has been reported as a natural inhibitor of soil N2O emissions. The aim of this study was to examine the potential for elevated ruminant urine HA concentrations to reduce N2O emissions, in situ, on an acidic heavy clay soil under poorly drained conditions (WFPS > 85%). A randomized complete block design experiment with three replications and four treatments was conducted using the closed-static-flux chamber methodology. The four treatments were applied inside the chambers: control with no artificial urine application (C), control artificial urine (U), and enriched artificial urine containing two rates of HA (55.8 and 90 mM, U+HA1, U+HA2). Soil inorganic-N, soil dissolved organic carbon (DOC), soil pH as well as N2O and methane (CH4) fluxes were monitored over a 79-day period. Although N2O emissions were not affected by the HA enriched urine treatments, U+HA2 positively affected the retention of N as NH4+ until day 3, when the soil pH dropped to values <5. Subsequently, as a consequence of rainfall events and soil acidification, it is likely that leaching or sorption onto clay reduced the efficacy of HA, masking any treatment differential effect on N2O emissions. Moreover, CH4 fluxes as well as DOC results reflected the soil anaerobic conditions which did not favour nitrification processes. Further research is needed to determine the fate of HA into the soil which might clarify the lack of an in situ effect of this compoun

Short-course Benznidazole treatment to reduce Trypanosoma cruzi parasitic load in women of reproductive age (BETTY): A non-inferiority randomized controlled trial study protocol

Background: Retrospective observational studies suggest that transmission of Trypanosoma cruzi does not occur in treated women when pregnant later in life. The level of parasitemia is a known risk factor for congenital transmission. Benznidazole (BZN) is the drug of choice for Preconceptional treatment to reduce parasitic load.The fear of treatment-related side effects limits the implementation of the Argentine guideline recommending BZN 60d/300 mg (or equivalent) treatment of T. cruzi seropositive women during the postpartum period to prevent transmission in a future pregnancy. A short and low dose BZN treatment might reduce major side effects and increase compliance, but its efficacy to reduce T. cruzi parasitic load compared to the standard 60d/300 mg course is not yet established. Clinical trials testing alternative BZN courses among women of reproductive age are urgently needed.Methods and design: We are proposing to perform a double-blinded, non-inferiority randomized controlled trial comparing a short low dose 30-day treatment with BZN 150 mg/day (30d/150 mg) vs. BZN 60d/300 mg. We will recruit not previously treated T. cruzi seropositive women with a live birth during the postpartum period in Argentina, randomize them at 6 months postpartum, and follow them up with the following specific aims:Specific aim 1: to measure the effect of BZN 30d/150 mg compared to 60d/300 mg preconceptional treatment on parasitic load measured by the frequency of positive Polymerase Chain Reaction (PCR) (primary outcome) and by real-time quantitative PCR (qPCR), immediately and 10 months after treatment.Specific aim 2: to measure the frequency of serious adverse events and/or any adverse event leading to treatment interruption.Fil: Cafferata, María L.. Instituto de Efectividad Clínica y Sanitaria; Argentina. Unicem; UruguayFil: Toscani, María A.. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Althabe, Fernando. Organizacion Mundial de la Salud; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: Belizan, Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: Bergel, Eduardo. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Berrueta, Mabel. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Capparelli, Edmund V.. University of California; Estados UnidosFil: Ciganda, Álvaro. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Danesi, Emmaría. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Centro Nacional de Diagnóstico e Investigaciones Endemo-epidémicas; ArgentinaFil: Dumonteil, Eric. University of Tulane; Estados UnidosFil: Gibbons, Luz. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Gulayin, Pablo Elías. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Herrera, Claudia. University of Tulane; Estados UnidosFil: Momper, Jeremiah D.. University of California; Estados UnidosFil: Rossi, Steven. University of California; Estados UnidosFil: Shaffer, Jeffrey G.. University of Tulane; Estados UnidosFil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Sosa-Estani, Sergio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: Stella, Candela B.. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Klein, Karen. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Buekens, Pierre. University of Tulane; Estados Unido

Meta-analysis of the detection of plant pigment concentrations using hyperspectral remotely sensed data

Passive optical hyperspectral remote sensing of plant pigments offers potential for understanding plant ecophysiological processes across a range of spatial scales. Following a number of decades of research in this field, this paper undertakes a systematic meta-analysis of 85 articles to determine whether passive optical hyperspectral remote sensing techniques are sufficiently well developed to quantify individual plant pigments, which operational solutions are available for wider plant science and the areas which now require greater focus. The findings indicate that predictive relationships are strong for all pigments at the leaf scale but these decrease and become more variable across pigment types at the canopy and landscape scales. At leaf scale it is clear that specific sets of optimal wavelengths can be recommended for operational methodologies: total chlorophyll and chlorophyll a quantification is based on reflectance in the green (550–560nm) and red edge (680–750nm) regions; chlorophyll b on the red, (630–660nm), red edge (670–710nm) and the near-infrared (800–810nm); carotenoids on the 500–580nm region; and anthocyanins on the green (550–560nm), red edge (700–710nm) and near-infrared (780–790nm). For total chlorophyll the optimal wavelengths are valid across canopy and landscape scales and there is some evidence that the same applies for chlorophyll a

The non-coding transcriptome as a dynamic regulator of cancer metastasis.

Since the discovery of microRNAs, non-coding RNAs (NC-RNAs) have increasingly attracted the attention of cancer investigators. Two classes of NC-RNAs are emerging as putative metastasis-related genes: long non-coding RNAs (lncRNAs) and small nucleolar RNAs (snoRNAs). LncRNAs orchestrate metastatic progression through several mechanisms, including the interaction with epigenetic effectors, splicing control and generation of microRNA-like molecules. In contrast, snoRNAs have been long considered "housekeeping" genes with no relevant function in cancer. However, recent evidence challenges this assumption, indicating that some snoRNAs are deregulated in cancer cells and may play a specific role in metastasis. Interestingly, snoRNAs and lncRNAs share several mechanisms of action, and might synergize with protein-coding genes to generate a specific cellular phenotype. This evidence suggests that the current paradigm of metastatic progression is incomplete. We propose that NC-RNAs are organized in complex interactive networks which orchestrate cellular phenotypic plasticity. Since plasticity is critical for cancer cell metastasis, we suggest that a molecular interactome composed by both NC-RNAs and proteins orchestrates cancer metastasis. Interestingly, expression of lncRNAs and snoRNAs can be detected in biological fluids, making them potentially useful biomarkers. NC-RNA expression profiles in human neoplasms have been associated with patients' prognosis. SnoRNA and lncRNA silencing in pre-clinical models leads to cancer cell death and/or metastasis prevention, suggesting they can be investigated as novel therapeutic targets. Based on the literature to date, we critically discuss how the NC-RNA interactome can be explored and manipulated to generate more effective diagnostic, prognostic, and therapeutic strategies for metastatic neoplasms

Intensificación del uso del agua: el riego suplementario y las oportunidades de contribuir al medio ambiente.

La mayor parte de los perjuicios ambientales encontrados en Uruguay vinculados al riego están directamente asociados a una mala adaptación local de sistemas desarrollados en otros países, a un inadecuado diseño del plan de riego, o a un incorrecto manejo del mismo. Ante el creciente uso del agua para riego en cultivos y pasturas, INIA se focaliza en la sostenibilidad de estos sistemas y en la disminución dei mpactos negativos sobre el ambiente