Search results for "F2"
showing 10 items of 316 documents
Gamma Ray Spectrum from Thermal Neutron Capture on Gadolinium-157
2018
International audience; We have measured the |$\gamma$|-ray energy spectrum from the thermal neutron capture, |${}^{157}$|Gd|$(n,\gamma)$|, on an enriched |$^{157}$|Gd target (Gd|$_{2}$|O|$_{3}$|) in the energy range from 0.11 MeV up to about 8 MeV. The target was placed inside the germanium spectrometer of the ANNRI detector at J-PARC and exposed to a neutron beam from the Japan Spallation Neutron Source (JSNS). Radioactive sources (|$^{60}$|Co, |$^{137}$|Cs, and |$^{152}$|Eu) and the |$^{35}$|Cl(|$n$|,|$\gamma$|) reaction were used to determine the spectrometer‘s detection efficiency for |$\gamma$| rays at energies from 0.3 to 8.5 MeV. Using a Geant4-based Monte Carlo simulation of …
Gamma Ray Spectra from Thermal Neutron Capture on Gadolinium-155 and Natural Gadolinium
2019
Natural gadolinium is widely used for its excellent thermal neutron capture cross section, because of its two major isotopes: $^{\rm 155}$Gd and $^{\rm 157}$Gd. We measured the $\gamma$-ray spectra produced from the thermal neutron capture on targets comprising a natural gadolinium film and enriched $^{\rm 155}$Gd (in Gd$_{2}$O$_{3}$ powder) in the energy range from 0.11 MeV to 8.0 MeV, using the ANNRI germanium spectrometer at MLF, J-PARC. The freshly analysed data of the $^{\rm 155}$Gd(n, $\gamma$) reaction are used to improve our previously developed model (ANNRI-Gd model) for the $^{\rm 157}$Gd(n, $\gamma$) reaction, and its performance confirmed with the independent data from the $^{\r…
Insect Cells for Heterologous Production of Recombinant Proteins
2010
Heterologous gene expression has become an indispensable and powerful tool for the production and subsequent functional analysis of proteins that are difficult to purify from their natural sources. Furthermore, it is the method of choice for the production of variants by introducing site-specific mutations into the DNA encoding the protein of interest. However, many systems are biased by disadvantages. The inability of bacteria to confer important post-translational modifications often results in functional failure of the recombinant protein. In addition, disulfide bonds are not formed properly in bacterial systems. Mammalian cells on the other hand modify properly, but they generally provi…
Una política educativa errática. El modelo de las enseñanzas artísticas de música
2017
El marco regulador escogido por nuestro legislador para las enseñanzas artísticas de música responde a un modelo de política educativa muy singular. En el presente artículo exponemos algunas de las bases, que se proyectan sobre la conformación de las enseñanzas y títulos que las refrendan, sobre el profesorado que las imparte y sobre las distintas opciones organizativas escogidas para los establecimientos docentes. Todo ello nos permite identificar los elementos sobre los que se ha construido este armazón educativo, señalando cuáles son las disfunciones que se producen dentro del sistema general.
Synthèse de nouveaux agents bimodaux hydrosolubles pour l'IRM, l'imagerie nucléaire, l'imagerie biphotonique et la génération de second harmonique
2015
The goal of my PhD studies was to synthesize new compounds for possible medical imaging applications. The first part of my thesis focused on the synthesis of heteroleptic ligands to achieve the chelation of two different metals aimed at addressing two types of medical imaging. We first synthesized porphyrins, which are well-known for the chelation of numerous transition metals. We focused on copper, whose copper-64 isotope is a β+ emitter usable in Positron Emission Tomography (PET). These porphyrins have been coupled with a DOTA derivative. This molecule, metallated with gadolinium, is well-known in Magnetic Resonance Imaging (MRI). Our compounds display encouraging relaxivities for MRI ap…
Value co-creation process and measurement in 4.0 SMEs: An exploratory research in a B2B marketing innovation context
2021
The purpose of this exploratory research is to contribute to the lack of empirical research exploring techniques and protocols that can be used to measure the level of value obtained from using these technologies in the various marketing processes and in a business-to-business (B2B) context. By doing so, firms operating in fast changing dynamic environments can develop the right means to continuously adapt, integrate, reconfigure, and redeploy resources and capabilities to become more competitive and disruptive in their offerings. The phenomenon of interest is described by applying a case study qualitative approach to three 4.0 companies which use virtual reality (VR)/augmented reality (AR)…
Modulation of Nrf2/ARE pathway by food polyphenols: a nutritional neuroprotective strategy for cognitive and neurodegenerative disorders
2011
In recent years, there has been a growing interest, supported by a large number of experimental and epidemi-ological studies, for the beneficial effects of some phenolic substances, contained in commonly used spices and herbs, in preventing various age-related pathologic conditions, ranging from cancer to neurodegenerative diseases. Although the exact mechanisms by which polyphenols promote these effects remain to be elucidated, several reports have shown their ability to stimulate a general xenobiotic response in the target cells, activating multiple defense genes. Data from our and other laboratories have previously demonstrated that curcumin, the yellow pigment of curry, strongly induces…
Membrane vesicles containing matrix metalloproteinase-9 and fibroblast growth factor-2 are released into the extracellular space from mouse mesoangio…
2010
Certain proteins, including fibroblast growth factor-2 (FGF-2) and matrix metalloproteinase-9 (MMP-9), have proved very effective in increasing the efficacy of mesoangioblast stem cell therapy in repairing damaged tissue. We provide the first evidence that mouse mesoangioblast stem cells release FGF-2 and MMP-9 in their active form through the production of membrane vesicles. These vesicles are produced and turned over continuously, but are stable for some time in the extracellular milieu. Mesoangioblasts shed membrane vesicles even under oxygen tensions that are lower than those typically used for cell culture and more like those of mouse tissues. These findings suggest that mesoangioblast…
Criterios relevantes e innovadores del Consejo de Transparencia de la Comunidad Valenciana
2019
espanolLa Comunidad Valenciana ha destacado en los ultimos anos en materia de transparencia. Sin embargo, su Consejo de Transparencia por diversos motivos ha quedado bastante oculto en su intensa labor. El estudio, analiza y expone las resoluciones y criterios mas innovadores y relevantes de este organo en sus cientos de resoluciones habidas desde inicios de 2016. Se considera que muchos de tales criterios deben ser cuanto menos conocidos y, en su caso, incorporarse o, cuanto menos, incitar al debate por especialistas y otros Consejos y autoridades de transparencia estatal o autonomicas. EnglishThe Valencian Community has highlighted in the last years in transparency. However, the intense w…
Eficiencia en la educación superior. Estudio empírico en universidades públicas de Colombia y España
2020
Resumen En las últimas décadas, las universidades de Iberoamérica han introducido nuevos esquemas de evaluación de calidad y rendición de cuentas, inspirados en el modelo de la nueva gestión pública (NGP). En este contexto, la eficiencia en el reparto de los fondos públicos y la obtención del máximo rendimiento posible son una prioridad. Así, medir la eficiencia en el sector público, y específicamente en la educación superior, se ha convertido en un desafío para la ciencia contable. El objetivo de este trabajo es una propuesta para el cálculo de índices de eficiencia con modelos de análisis envolvente de datos (DEA), introduciendo un paso previo a través del análisis de correlación canónica…