955 resultados para Solid,Blockchain,Web decentralizzato,BCSolid,Trust Access
Resumo:
Cell-based therapies have demonstrated potency and efficacy as cancer treatment modalities. T cells can be dichotomized by their T cell receptor (TCR) complexes where alpha/beta T cells (95% of T cells) and gamma/delta T cells (+T cells proliferated to clinically significant numbers and ROR1+ tumor cells were effectively targeted and killed by both ROR1-specific CAR+ T cell populations, although ROR1RCD137 were superior to ROR1RCD28 in clearance of leukemia xenografts in vivo. The second specific aim focused on generating bi-specific CD19-specific CAR+ gamma/delta T cells with polyclonal TCRgamma/delta repertoire on CD19+ artificial antigen presenting cells (aAPC). Enhanced cytolysis of CD19+ leukemia was observed by CAR+ gamma/delta T cells compared to CARneg gamma/delta T cells, and leukemia xenografts were significantly reduced compared to control mice in vivo. The third specific aim looked at the broad anti-tumor effects of polyclonal gamma/delta T cells expanded on aAPC without CAR+ T cells, where Vdelta1, Vdelta2, and Vdelta3 populations had naïve, effector memory, and central memory phenotypes and effector function strength in the following order: Vdelta2>Vdelta3>Vdelta1. Polyclonal gamma/delta T cells eliminated ovarian cancer xenografts in vivo and increased survival compared to control mice. Thus, translating these methodologies to clinical trials will provide cancer patients novel, safe, and effective options for their treatment.
Resumo:
Time variable gravity fields, reflecting variations of mass distribution in the system Earth is one of the key parameters to understand the changing Earth. Mass variations are caused either by redistribution of mass in, on or above the Earth's surface or by geophysical processes in the Earth's interior. The first set of observations of monthly variations of the Earth gravity field was provided by the US/German GRACE satellite mission beginning in 2002. This mission is still providing valuable information to the science community. However, as GRACE has outlived its expected lifetime, the geoscience community is currently seeking successor missions in order to maintain the long time series of climate change that was begun by GRACE. Several studies on science requirements and technical feasibility have been conducted in the recent years. These studies required a realistic model of the time variable gravity field in order to perform simulation studies on sensitivity of satellites and their instrumentation. This was the primary reason for the European Space Agency (ESA) to initiate a study on ''Monitoring and Modelling individual Sources of Mass Distribution and Transport in the Earth System by Means of Satellites''. The goal of this interdisciplinary study was to create as realistic as possible simulated time variable gravity fields based on coupled geophysical models, which could be used in the simulation processes in a controlled environment. For this purpose global atmosphere, ocean, continental hydrology and ice models were used. The coupling was performed by using consistent forcing throughout the models and by including water flow between the different domains of the Earth system. In addition gravity field changes due to solid Earth processes like continuous glacial isostatic adjustment (GIA) and a sudden earthquake with co-seismic and post-seismic signals were modelled. All individual model results were combined and converted to gravity field spherical harmonic series, which is the quantity commonly used to describe the Earth's global gravity field. The result of this study is a twelve-year time-series of 6-hourly time variable gravity field spherical harmonics up to degree and order 180 corresponding to a global spatial resolution of 1 degree in latitude and longitude. In this paper, we outline the input data sets and the process of combining these data sets into a coherent model of temporal gravity field changes. The resulting time series was used in some follow-on studies and is available to anybody interested.
Resumo:
En este ensayo reflexionamos sobre los desafíos tecnológicos, económicos, académicos y políticos que implica la edición científica en formato digital para los investigadores argentinos en Ciencias Sociales y Humanas. Basándonos en la trayectoria de la Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata en la materia, proponemos que el trabajo interdisciplinario, el acceso abierto y la revisión por pares son los pilares fundamentales para llevar adelante una revista científica publicada en la web desde una unidad académica, es decir, desarrollada por el trabajo ad honorem de docentes-investigadores y sostenida económicamente con el presupuesto universitario
Resumo:
En este ensayo reflexionamos sobre los desafíos tecnológicos, económicos, académicos y políticos que implica la edición científica en formato digital para los investigadores argentinos en Ciencias Sociales y Humanas. Basándonos en la trayectoria de la Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata en la materia, proponemos que el trabajo interdisciplinario, el acceso abierto y la revisión por pares son los pilares fundamentales para llevar adelante una revista científica publicada en la web desde una unidad académica, es decir, desarrollada por el trabajo ad honorem de docentes-investigadores y sostenida económicamente con el presupuesto universitario
Resumo:
The outer western Crimean shelf of the Black Sea is a natural laboratory to investigate effects of stable oxic versus varying hypoxic conditions on seafloor biogeochemical processes and benthic community structure. Bottom-water oxygen concentrations ranged from normoxic (175 µmol O2/L) and hypoxic (< 63 µmol O2/L) or even anoxic/sulfidic conditions within a few kilometers' distance. Variations in oxygen concentrations between 160 and 10 µmol/L even occurred within hours close to the chemocline at 134 m water depth. Total oxygen uptake, including diffusive as well as fauna-mediated oxygen consumption, decreased from 15 mmol/m**2/d on average in the oxic zone, to 7 mmol/m**2/d on average in the hypoxic zone, correlating with changes in macrobenthos composition. Benthic diffusive oxygen uptake rates, comprising respiration of microorganisms and small meiofauna, were similar in oxic and hypoxic zones (on average 4.5 mmol/m**2/d), but declined to 1.3 mmol/m**2/d in bottom waters with oxygen concentrations below 20 µmol/L. Measurements and modeling of porewater profiles indicated that reoxidation of reduced compounds played only a minor role in diffusive oxygen uptake under the different oxygen conditions, leaving the major fraction to aerobic degradation of organic carbon. Remineralization efficiency decreased from nearly 100 % in the oxic zone, to 50 % in the oxic-hypoxic zone, to 10 % in the hypoxic-anoxic zone. Overall, the faunal remineralization rate was more important, but also more influenced by fluctuating oxygen concentrations, than microbial and geochemical oxidation processes.
Resumo:
In this study we investigate benthic phosphorus cycling in recent continental margin sediments at three sites off the Namibian coastal upwelling area. Examination of the sediments reveals that organic and biogenic phosphorus are the major P-containing phases preserved. High Corg/Porg ratios just at the sediment surface suggest that the preferential regeneration of phosphorus relative to that of organic carbon has either already occurred on the suspension load or that the organic matter deposited at these sites is already rather refractory. Release of phosphate in the course of benthic microbial organic matter degradation cannot be identified as the dominating process within the observed internal benthic phosphorus cycle. Dissolved phosphate and iron in the pore water are closely coupled, showing high concentrations below the oxygenated surface layer of the sediments and low concentrations at the sediment-water interface. The abundant presence of Fe(III)-bound phosphorus in the sediments document the co-precipitation of both constituents as P-containing iron (oxyhydr)oxides. However, highly dissolved phosphate concentrations in pore waters cannot be explained, neither by simple mass balance calculations nor by the application of an established computer model. Under the assumption of steady state conditions, phosphate release rates are too high as to be balanced with a solid phase reservoir. This discrepancy points to an apparent lack of solid phase phosphorus at sediment depth were suboxic conditions prevail. We assume that the known, active, fast and episodic particle mixing by burrowing macrobenthic organisms could repeatedly provide the microbially catalyzed processes of iron reduction with authigenic iron (oxyhydro)oxides from the oxic surface sediments. Accordingly, a multiple internal cycling of phosphate and iron would result before both elements are buried below the iron reduction zone.
Resumo:
En este ensayo reflexionamos sobre los desafíos tecnológicos, económicos, académicos y políticos que implica la edición científica en formato digital para los investigadores argentinos en Ciencias Sociales y Humanas. Basándonos en la trayectoria de la Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata en la materia, proponemos que el trabajo interdisciplinario, el acceso abierto y la revisión por pares son los pilares fundamentales para llevar adelante una revista científica publicada en la web desde una unidad académica, es decir, desarrollada por el trabajo ad honorem de docentes-investigadores y sostenida económicamente con el presupuesto universitario