Evaluación de enmiendas orgánicas en el suelo y en el cultivo de tomate (Lycopersicum esculentum Mill.)

Los sistemas productivos intensivos conforme se realizan en el denominado Cinturón Hortícola Metropolitano, donde se emplaza el presente estudio, tienen a la degradación edáfica como uno de los factores de mayor responsabilidad en la pérdida de sustentabilidad social, económica, productiva y ambiental. El objetivo de este estudio fue evaluar los efectos de la aplicación de enmiendas orgánicas sobre las propiedades físicas del suelo y en el cultivo de tomate (Lycopersicum esculentum Mill.) en invernadero tipo capilla perteneciente a la Estación Experimental Gorina, localidad: Joaquín Gorina, Partido de La Plata. Bs. As. Argentina. El diseño experimental fue bloques al azar con 4 repeticiones. Los tratamientos: Testigo (T), suelo sin enmiendas orgánicas; T2, estiércol de cama de pollo sin compostar en dosis aproximada equivalente a 30-40 tn.ha-1 uso frecuente en la región de estudio; T3, compost de cama de pollo en dosis equivalente a T2 y T4, compost en doble dosis del T3. Las enmiendas fueron agregadas 8/2015. Se estudió el suelo en dos profundidades, superficial (0-10 cm) y subsuperficial (10-20 cm), toma de muestras 3/2016. Se analizaron del suelo: Humedad gravimétrica, Nitrógeno total, Materia orgánica, Estabilidad Estructural y Conductividad Hidráulica. En planta las variables de crecimiento: altura de planta, largo y ancho de primera hoja desarrollada, diámetro del tallo y número de racimos florales. Se midió el rendimiento del cultivo separando por calidad y peso de fruto. Los resultados se analizaron estadísticamente por ANOVA y mediante el Test de Tukey. El Tratamiento con compost en doble dosis fue significativamente mayor que el Testigo en el contenido de Nt y Materia orgánica, en el estrato superficial. Asimismo, el T4 presentó mayor estabilidad estructural y conductividad hidráulica subsuperficialmente. No se observaron diferencias en el rendimiento ni en las variables de crecimiento del tomate, aunque en casi todos las variable de desarrollo presentaron como tendencia T<T1<T2<T3<T4. La cama de pollo fresca no mejoró la estabilidad estructural ni la conductividad hidráulica ni condujo a mejoras en el rendimiento del tomate.Facultad de Ciencias Agrarias y Forestale

Crowd Research at School: Crossing Flows

It has become widely known that when two flows of pedestrians cross stripes emerge spontaneously by which the pedestrians of the two walking directions manage to pass each other in an orderly manner. In this work, we report about the results of an experiment on crossing flows which has been carried out at a German school. These results include that previously reported high flow volumes on the crossing area can be confirmed. The empirical results are furthermore compared to the results of a simulation model which succesfully could be calibrated to catch the specific properties of the population of participants.Comment: contribution to proceedings of Traffic and Granular Flow 2013 held in J\"ulich, German

The SPACE Computer Code for Analyzing the International Space Station Electrical Power System: Past, Present, and Future

The System Power Analysis for Capability Evaluation (SPACE) computer code was initially developed by NASA in 1988 to assess the Space Station Freedom electric power system and later adapted to support contractor electrical power system capability analyses for the International Space Station (ISS). Over time, the code has supported many efforts such as ISS redesign activities in the early 1990s, assessment of time-phased loads against power system operating limits for future ISS assembly flights (including Certification of Flight Readiness reviews by the ISS program office), and determining the optimum solar array gimbal positions while respecting keep-out zones which minimize both solar array contamination and structural loads. The code has been validated by comparisons with ISS on-orbit data in multiple validation episodes. Recent updates to the code include the incorporation of a Lithium-Ion battery model in addition to the Nickel Hydrogen battery model and modifications to the solar array degradation model to better match on-orbit test results. SPACE has also been extended beyond the ISS to include modeling of the Orion Multi-Purpose Crew Vehicle electrical power system (SPACE-MPCV) and Mars Surface Electrical Power Systems (MSEPS). Portions of SPACE were integrated with a trajectory code to form a Solar Electric Propulsion Simulation (SEPSim), which can be used for analyzing solar electric propulsion missions. In addition, SPACE methods and subroutines have been adapted to a multitude of other projects. This paper summarizes the initial code development and subsequent code utilization in the context of the overall ISS program development and on-orbit operations. Recent updates and results from the code are discussed, including preliminary analyses for the Orion power system

Efecto del óxido nítrico exógeno sobre el crecimiento de plantas de trigo durante la restricción de fosfato

El objetivo de este trabajo fue evaluar el efecto del NO exógeno sobre el desempeño de plantas de trigo sometidas a restricción de P y su influencia sobre la eficiencia del uso del mismo.Facultad de Ciencias Agrarias y Forestale

Efecto del óxido nítrico exógeno sobre el crecimiento de plantas de trigo durante la restricción de fosfato

El objetivo de este trabajo fue evaluar el efecto del NO exógeno sobre el desempeño de plantas de trigo sometidas a restricción de P y su influencia sobre la eficiencia del uso del mismo.Facultad de Ciencias Agrarias y Forestale

Efecto del óxido nítrico exógeno sobre el crecimiento de plantas de trigo durante la restricción de fosfato

El objetivo de este trabajo fue evaluar el efecto del NO exógeno sobre el desempeño de plantas de trigo sometidas a restricción de P y su influencia sobre la eficiencia del uso del mismo.Facultad de Ciencias Agrarias y Forestale

NOX4-derived ROS are neuroprotective by balancing intracellular calcium stores

Hyperexcitability is associated with neuronal dysfunction, cellular death, and consequently neurodegeneration. Redox disbalance can contribute to hyperexcitation and increased reactive oxygen species (ROS) levels are observed in various neurological diseases. NOX4 is an NADPH oxidase known to produce ROS and might have a regulating function during oxidative stress. We, therefore, aimed to determine the role of NOX4 on neuronal firing, hyperexcitability, and hyperexcitability-induced changes in neural network function. Using a multidimensional approach of an in vivo model of hyperexcitability, proteomic analysis, and cellular function analysis of ROS, mitochondrial integrity, and calcium levels, we demonstrate that NOX4 is neuroprotective by regulating ROS and calcium homeostasis and thereby preventing hyperexcitability and consequently neuronal death. These results implicate NOX4 as a potential redox regulator that is beneficial in hyperexcitability and thereby might have an important role in neurodegeneration.</p

Leveraging Spatial Variation in Tumor Purity for Improved Somatic Variant Calling of Archival Tumor Only Samples

Archival tumor samples represent a rich resource of annotated specimens for translational genomics research. However, standard variant calling approaches require a matched normal sample from the same individual, which is often not available in the retrospective setting, making it difficult to distinguish between true somatic variants and individual-specific germline variants. Archival sections often contain adjacent normal tissue, but this tissue can include infiltrating tumor cells. As existing comparative somatic variant callers are designed to exclude variants present in the normal sample, a novel approach is required to leverage adjacent normal tissue with infiltrating tumor cells for somatic variant calling. Here we present lumosVar 2.0, a software package designed to jointly analyze multiple samples from the same patient, built upon our previous single sample tumor only variant caller lumosVar 1.0. The approach assumes that the allelic fraction of somatic variants and germline variants follow different patterns as tumor content and copy number state change. lumosVar 2.0 estimates allele specific copy number and tumor sample fractions from the data, and uses a to model to determine expected allelic fractions for somatic and germline variants and to classify variants accordingly. To evaluate the utility of lumosVar 2.0 to jointly call somatic variants with tumor and adjacent normal samples, we used a glioblastoma dataset with matched high and low tumor content and germline whole exome sequencing data (for true somatic variants) available for each patient. Both sensitivity and positive predictive value were improved when analyzing the high tumor and low tumor samples jointly compared to analyzing the samples individually or in-silico pooling of the two samples. Finally, we applied this approach to a set of breast and prostate archival tumor samples for which tumor blocks containing adjacent normal tissue were available for sequencing. Joint analysis using lumosVar 2.0 detected several variants, including known cancer hotspot mutations that were not detected by standard somatic variant calling tools using the adjacent tissue as presumed normal reference. Together, these results demonstrate the utility of leveraging paired tissue samples to improve somatic variant calling when a constitutional sample is not available

Different niches for stem cells carrying the same oncogenic driver affect pathogenesis and therapy response in myeloproliferative neoplasms

Aging facilitates the expansion of hematopoietic stem cells (HSCs) carrying clonal hematopoiesis-related somatic mutations and the development of myeloid malignancies, such as myeloproliferative neoplasms (MPNs). While cooperating mutations can cause transformation, it is unclear whether distinct bone marrow (BM) HSC-niches can influence the growth and therapy response of HSCs carrying the same oncogenic driver. Here we found different BM niches for HSCs in MPN subtypes. JAK-STAT signaling differentially regulates CDC42-dependent HSC polarity, niche interaction and mutant cell expansion. Asymmetric HSC distribution causes differential BM niche remodeling: sinusoidal dilation in polycythemia vera and endosteal niche expansion in essential thrombocythemia. MPN development accelerates in a prematurely aged BM microenvironment, suggesting that the specialized niche can modulate mutant cell expansion. Finally, dissimilar HSC-niche interactions underpin variable clinical response to JAK inhibitor. Therefore, HSC-niche interactions influence the expansion rate and therapy response of cells carrying the same clonal hematopoiesis oncogenic driver

Different niches for stem cells carrying the same oncogenic driver affect pathogenesis and therapy response in myeloproliferative neoplasms

Aging facilitates the expansion of hematopoietic stem cells (HSCs) carrying clonal hematopoiesis-related somatic mutations and the development of myeloid malignancies, such as myeloproliferative neoplasms (MPNs). While cooperating mutations can cause transformation, it is unclear whether distinct bone marrow (BM) HSC-niches can influence the growth and therapy response of HSCs carrying the same oncogenic driver. Here we found different BM niches for HSCs in MPN subtypes. JAK-STAT signaling differentially regulates CDC42-dependent HSC polarity, niche interaction and mutant cell expansion. Asymmetric HSC distribution causes differential BM niche remodeling: sinusoidal dilation in polycythemia vera and endosteal niche expansion in essential thrombocythemia. MPN development accelerates in a prematurely aged BM microenvironment, suggesting that the specialized niche can modulate mutant cell expansion. Finally, dissimilar HSC-niche interactions underpin variable clinical response to JAK inhibitor. Therefore, HSC-niche interactions influence the expansion rate and therapy response of cells carrying the same clonal hematopoiesis oncogenic driver