19 research outputs found
Direct observation of the influence of the As-Fe-As angle on the Tc of superconducting SmFeAsOF
The electrical resistivity, crystalline structure and electronic properties
calculated from the experimentally measured atomic positions of the compound
SmFeAsOF have been studied up to pressures ~20GPa. The
correlation between the pressure dependence of the superconducting transition
temperature (Tc) and crystallographic parameters on the same sample shows
clearly that a regular FeAs tetrahedron maximizes Tc, through
optimization of carrier transfer to the FeAs planes as indicated by the
evolution of the electronic band structures.Comment: 15pages, 4 figure
Correlated pressure effects on structure and superconductivity in LaFeAsO0.9F0.1
We have studied the structural and superconductivity properties of the
compound LaFeAsO0.9F0.1 under pressures up to 32GPa using synchrotron radiation
and diamond anvil cells. We obtain an ambient pressure bulk modulus K_0 =
78(2)GPa, compressibility comparable to some cuprates. At high pressures, the
sample is in the overdoped region, with a linear decrease with pressure
variation of the superconducting transition temperature.Comment: 15 pages, 4 figures, 1 tabl
Inhibition of the autocrine IL-6-JAK2-STAT3-calprotectin axis as targeted therapy for HR-/HER2+ breast cancers
HER2-positive (HER2(+)) breast adenocarcinomas are a heterogeneous group in which hormone receptor (HR) status influences therapeutic decisions and patient outcome. By combining genome-wide RNAi screens with regulatory network analysis, we identified STAT3 as a critically activated master regulator of HR(-)/HER2(+) tumors, eliciting tumor dependency in these cells. Mechanistically, HR(-)/HER2(+) cells secrete high levels of the interleukin-6 (IL-6) cytokine, inducing the activation of STAT3, which in turn promotes a second autocrine stimulus to increase S100A8/9 complex (calprotectin) production and secretion. Increased calprotectin levels activate signaling pathways involved in proliferation and resistance. Importantly, we demonstrated that inhibition of the IL-6-Janus kinase 2 (JAK2)-STAT3-calprotectin axis with FDA-approved drugs, alone and in combination with HER2 inhibitors, reduced the tumorigenicity of HR(-)/HER2(+) breast cancers, opening novel targeted therapeutic opportunities
White Paper 1: New foundations for a sustainable global society
Coordinación: Eduardo Moyano Estrada; Tomás García Azcárate.This volume is focused on the axis “New foundations for a sustainable global society”, and refers to the important process of global change that affects all dimensions of society, disrupting the context in which scientific work has been developed in recent decades. It is a process of change not comparable to what happened decades ago, mainly due to its breadth, multidimensionality and interdependence, and also to the fact that this process manifests itself simultaneously in many areas, territories and social groups. Its analysis therefore requires carrying out a convergence exercise between areas and lines of research, betting on a multidisciplinary approach, since both “globalization” and “sustainability” are, concepts that affect society, as a whole.Peer reviewe
Carotenoides en agroalimentación y salud
Los carotenoides son compuestos especiales; si bien es común referirse a ellos como
pigmentos, lo cierto es que son compuestos de gran versatilidad e importancia en la
naturaleza. Más específicamente, son de gran interés en agroalimentación y salud.
Así, por ejemplo, son pigmentos naturales y por lo tanto tienen un importante papel en
la elección de alimentos por parte de los consumidores. Asimismo, algunos de ellos
son precursores de la vitamina A. Sin embargo, que cada vez exista más interés en los
carotenoides en este contexto se debe en gran parte a muchos estudios de distinta
naturaleza que indican que pueden proporcionar beneficios para la salud. Su interés
en alimentación funcional es por lo tanto indudable.
En este libro se refleja la experiencia en carotenoides de un gran número de
profesionales de la región iberoamericana. En conjunto, se ofrece una visión general
de la investigación sobre estos compuestos en agroalimentación y salud. Los autores
son miembros de la red ibercarot (http://carotenoides.us.es), que tiene entre sus
objetivos conformar una red estable y funcional de profesionales que aúnen esfuerzos
en pos de identificar nuevas fuentes de carotenoides de interés nutricional, mejorar su
producción y aumentar el valor de los productos que los contengan.
Me gustaría agradecer a todas y cada una de las personas que han contribuido de
una u otra forma a que este libro sea una realidad. Todos esperamos que sea de
ayuda para personas interesadas en los temas desarrollados. Gracias especialmente
al Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (Cyted, http://
www.cyted.org/) que, con su apoyo económico a la red ibercarot, ha hecho posible
que varias decenas de equipos interaccionen en torno a temas de interés común para
contribuir al desarrollo a distintos niveles de la región iberoamericana.RED TEMÁTICA IBERCAROT (referencia 112RT445) http://carotenoides.us.es
PROGRAMA IBEROAMERICANO DE CIENCIA Y TECNOLOGIA PARA EL DESARROLLO – CYTEDPeer reviewe
Nanostructure surveys of macroscopic specimens by small-angle scattering tensor tomography
The mechanical properties of many materials are based on the macroscopic arrangement and orientation of their nanostructure. This nanostructure can be ordered over a range of length scales. In biology, the principle of hierarchical ordering is often used to maximize functionality, such as strength and robustness of the material, while minimizing weight and energy cost. Methods for nanoscale imaging provide direct visual access to the ultrastructure (nanoscale structure that is too small to be imaged using light microscopy), but the field of view is limited and does not easily allow a full correlative study of changes in the ultrastructure over a macroscopic sample. Other methods of probing ultrastructure ordering, such as small-angle scattering of X-rays or neutrons, can be applied to macroscopic samples; however, these scattering methods remain constrained to two-dimensional specimens or to isotropically oriented ultrastructures. These constraints limit the use of these methods for studying nanostructures with more complex orientation patterns, which are abundant in nature and materials science. Here, we introduce an imaging method that combines small-angle scattering with tensor tomography to probe nanoscale structures in three-dimensional macroscopic samples in a non-destructive way. We demonstrate the method by measuring the main orientation and the degree of orientation of nanoscale mineralized collagen fibrils in a human trabecula bone sample with a spatial resolution of 25 micrometres. Symmetries within the sample, such as the cylindrical symmetry commonly observed for mineralized collagen fibrils in bone, allow for tractable sampling requirements and numerical efficiency. Small-angle scattering tensor tomography is applicable to both biological and materials science specimens, and may be useful for understanding and characterizing smart or bio-inspired materials. Moreover, because the method is non-destructive, it is appropriate for in situ measurements and allows, for example, the role of ultrastructure in the mechanical response of a biological tissue or manufactured material to be studie