Photodynamic therapy with 5-methylaminolevulinic acid in the treatment of multiple warts of the face.

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Surface symmetry-breaking and strain effects on orbital occupancy in transition metal perovskite epitaxial films

The electron occupancy of 3d-orbitals determines the properties of transition metal oxides. This can be achieved, for example, through thin-film heterostructure engineering of ABO(3) oxides, enabling emerging properties at interfaces. Interestingly, epitaxial strain may break the degeneracy of 3d-e(g) and t(2g) orbitals, thus favoring a particular orbital filling with consequences for functional properties. Here we disclose the effects of symmetry breaking at free surfaces of ABO(3) perovskite epitaxial films and show that it can be combined with substrate-induced epitaxial strain to tailor at will the electron occupancy of in-plane and out-of-plane surface electronic orbitals. We use X-ray linear dichroism to monitor the relative contributions of surface, strain and atomic terminations to the occupancy of 3z(2)-r(2) and x(2)-y(2) orbitals in La(2/3)Sr(1/3)MnO(3) films. These findings open the possibility of an active tuning of surface electronic and magnetic properties as well as chemical properties (catalytic reactivity, wettability and so on)

Symmetry of the Fermi surface and evolution of the electronic structure across the paramagnetic-helimagnetic transition in MnSi/Si(111)

MnSi has been extensively studied for five decades, nonetheless detailed information on the Fermi surface (FS) symmetry is still lacking. This missed information prevented from a comprehensive understanding the nature of the magnetic interaction in this material. Here, by performing angle-resolved photoemission spectroscopy on high-quality MnSi films epitaxially grown on Si(111), we unveil the FS symmetry and the evolution of the electronic structure across the paramagnetic-helimagnetic transition at T$_C$ $\sim$ 40 K, along with the appearance of sharp quasiparticle emission below T$_C$. The shape of the resulting FS is found to fulfill robust nesting effects. These effects can be at the origin of strong magnetic fluctuations not accounted for by state-of-art quasiparticle self-consistent GW approximation. From this perspective, the unforeseen quasiparticle damping detected in the paramagnetic phase and relaxing only below T$_C$, along with the persistence of the d-bands splitting well above T$_C$, at odds with a simple Stoner model for itinerant magnetism, open the search for exotic magnetic interactions favored by FS nesting and affecting the quasiparticles lifetime

Fuera de programa : La ausencia de los sectores vulnerables en la formación jurídica

El artículo aborda la problemática de la inserción en la formación profesional de los abogados de temáticas vinculadas con sectores vulnerables y su relación con el Derecho, en particular en lo que hace al sector campesino, la niñez y adolescencia y los jóvenes de sectores empobrecidos y marginados. Sobre la base del análisis de la bibliografía, de los programas de la carrera y de entrevistas a docentes y estudiantes avanzados, se advierte una inclusión insuficiente de estas temáticas tanto desde el punto de vista formal, en los programas de estudio, como en su abordaje efectivo durante el desarrollo de las respectivas asignaturas. Las conclusiones, en términos de los déficits que implican en la formación de profesionales comprometidos con la realidad, constituyen una invitación a reflexionar respecto de qué conocimiento generamos y transmitimos, quiénes son los destinatarios directos e indirectos de la educación universitaria y, en definitiva, qué tan dispuestos estamos a colaborar desde lo propio de la labor universitaria, con la construcción de una sociedad más justa.The article deals with the insertion in the law student´s professional training of themes linked to vulnerable sectors and their relationship with the Law, particularly the writing about peasant’s sector, childhood and adolescence as well as poor and marginal young people. Based on the analysis that the researchers have been making of bibliography, academic programs, and interviewing teachers and advanced students of Law School, it is perceived an unsatisfactory insertion of the topics above in the Law Students academic formation. The conclusion about this kind of deficit in the training of professionals committed to the reality is an invitation to make a reflection about what kind of knowledge we are generating and transmitting, who are the direct and indirect receiver of university education, and how available we are to collaborate through our work in university to build a society more fair and equal.Instituto de Cultura Jurídica (ICJ

Fuera de programa: La ausencia de los sectores vulnerables en la formación jurídica

El artículo aborda la problemática de la inserción en la formación profesional de los abogados de temáticas vinculadas con sectores vulnerables y su relación con el Derecho, en particular en lo que hace al sector campesino, la niñez y adolescencia y los jóvenes de sectores empobrecidos y marginados. Sobre la base del análisis de la bibliografía, de los programas de la carrera y de entrevistas a docentes y estudiantes avanzados, se advierte una inclusión insuficiente de estas temáticas tanto desde el punto de vista formal, en los programas de estudio, como en su abordaje efectivo durante el desarrollo de las respectivas asignaturas. Las conclusiones, en términos de los déficits que implican en la formación de profesionales comprometidos con la realidad, constituyen una invitación a reflexionar respecto de qué conocimiento generamos y transmitimos, quiénes son los destinatarios directos e indirectos de la educación universitaria y, en definitiva, qué tan dispuestos estamos a colaborar desde lo propio de la labor universitaria, con la construcción de una sociedad más justa

Understanding the effects of Cr doping in rutile TiO₂ by DFT calculations and X-ray spectroscopy

The effects of Cr on local environment and electronic structure of rutile TiO₂ are studied combining theoretical and experimental approaches. Neutral and negatively charged substitutional Cr impurities Cr_(Ti)(0)* and Cr_(Ti)(-1)* as well as Cr-oxygen vacancy complex 2Cr_(Ti) + V₀ are studied by the density functional theory (DFT) within the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE) functional. Experimental results based on X-Ray absorption spectroscopy (XAS) and X-Ray photoelectron spectroscopy (XPS) performed on Cr doped TiO₂ at the Synchrotron facility were compared to the theoretical results. It is shown that the electrons of the oxygen vacancy tend to be localized at the t_(2g) states of the Cr ions in order to reach the stable oxidation state of Cr(3+)*. Effects of Cr on crystal field (CF) and structural distortions in the rutile TiO₂ cell were analyzed by the DFT calculations and XAS spectra revealing that the CF and tetragonal distortions in TiO₂ are very sensitive to the concentration of Cr

Ultrafast carrier phonon dynamics in NaOH-reacted graphite oxide film

NaOH-reacted graphite oxide film was prepared by decomposing epoxy groups in graphite oxide into hydroxyl and -ONa groups with NaOH solution. Ultrafast carrier dynamics of the sample were studied by time-resolved transient differential reflection (\DeltaR/R). The data show two exponential relaxation processes. The slow relaxation process (\sim2ps) is ascribed to low energy acoustic phonon mediated scattering. The electron-phonon coupling and first-principles calculation results demonstrate that - OH and -ONa groups in the sample are strongly coupled. Thus, we attribute the fast relaxation process (\sim0.17ps) to the coupling of hydroxyl and -ONa groups in the sample

UHV Deposition and Characterization of a Mononuclear Iron(III) \u3b2-diketonate Complex on Au(111)

The adsorption of the sterically hindered \u3b2-diketonate complex Fe(dpm)3, where Hdpm = dipivaloylmethane, on Au(111) was investigated by ultraviolet photoelectron spectroscopy (UPS) and scanning tunnelling microscopy (STM). The high volatility of the molecule limited the growth of the film to a few monolayers. While UPS evidenced the presence of the \u3b2-diketonate ligands on the surface, the integrity of the molecule on the surface could not be assessed. The low temperature STM images were more informative and at submonolayer coverage they showed the presence of regular domains characterized by a flat morphology and height of 480.3 nm. Along with these domains, tetra-lobed features adsorbed on the kinks of the herringbone were also observed. DFT-simulated images of the pristine molecule and its possible decomposition products allowed to assess the partial fragmentation of Fe(dpm)3 upon adsorption on the Au(111) surface. Structural features with intact molecules were only observed for the saturation coverage. An ex situ prepared thick film of the complex was also investigated by X-ray magnetic circular dichroism (XMCD) and features typical of high-spin iron(III) in octahedral environment were observed