Fundamental studies on the adsorption and reactivity of surface porphyrins

Los materiales híbridos compuestos de moléculas orgánicas depositadas sobre sustratos sólidos tienen una importancia central en el diseño de catalizadores, sensores, dispositivos optoelectrónicos y celdas solares. Las porfirinas constituyen un bloque de construcción ideal debido a su capacidad para enlazar y liberar moléculas con alta especificidad, a que pueden actuar como centros activos en reacciones catalíticas y a que pueden mediar procesos de transferencia de energía que involucren fotones en el visible. Por lo tanto, el estudio de la interacción de porfirinas con superficies sólidas es de gran relevancia tanto académica como tecnológica, razón por la cual ha despertado mucho interés en las últimas décadas. Sin embargo, al momento de comenzar esta tesis, la mayor parte de los estudios se habían centrado en el estudio de moléculas adsorbidas en superficies metálicas y solo en pocos casos se estudió la interacción con superficies de óxidos. Durante el desarrollo de esta tesis doctoral se estudió la interacción de un conjunto amplio de porfirinas modificadas con distintos grupos funcionales con autoensamblados moleculares y con las superficies de rutilo TiO2(110) y Au(111). Utilizando fundamentalmente espectroscopías fotoelectrónicas y de absorción de rayos X, se estudió el modo de enlace de las moléculas, su geometría de adsorción y su estructura electrónica. A su vez, se estudió la reactividad química del centro del macrociclo para la inserción de iones, su intercambio y su pérdida. Nuestras investigaciones han permitido determinar la importancia que tiene el número y la posición de los grupos funcionales en el anillo del macrociclo en la geometría de adsorción de la molécula y los factores que determinan la reactivad química del macrociclo. Los resultados presentados en este trabajo constituyen un avance importante en el campo de la química de superficies de las porfirinas.Hybrid materials composed of organic molecules deposited on solid substrates are of central importance in the design of catalysts, sensors, optoelectronic devices and solar cells. Porphyrins constitute an ideal building block due to their ability to bind and release molecules with high specificity, because they can act as active centers in catalytic reactions and because they can mediate energy transfer processes that involve photons in the visible region. Therefore, the interaction of porphyrins with solid surfaces, which is of great academic and technological relevance, has been studied extensively in recent decades. However, when this thesis started, most of the studies had focused on the study of molecules adsorbed on metal surfaces and only in a few cases the interaction with oxide surfaces was studied. During the development of this doctoral thesis, the interaction of modified porphyrins with different functional groups with molecular self-assembled monolayers and with the rutile TiO2(110) and the Au(111) surfaces was studied. Using mainly X-ray photoelectron and absorption spectroscopies, the binding mode of the molecules, their adsorption geometry and their electronic structure were studied. Furthermore, chemical reactions involving insertion, exchange and loss of metal ions from the macrocycle center were studied. Our investigations shed new light into the importance of the number and position of functional groups in the macrocycle ring in the adsorption geometry of the molecule and the factors that determine the chemical reactivity of the macrocycle. The results presented in this work constitute an important advance in the field of porphyrins surface chemistry.Fil: Fernández, Cynthia Carolina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Electronic Structure of a Self-Assembled Monolayer with Two Surface Anchors: 6-Mercaptopurine on Au(111)

The electronic structure of aromatic and aliphatic thiols on Au(111) has been extensively studied in relation to possible applications in molecular electronics. In this work, the effect on the electronic structure of an additional anchor to the S-Au bond using 6-mercaptopurine as a model system has been investigated. Results from X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and density functional theory (DFT) confirm that this molecule adsorbs on Au(111) with S-Au and iminic N-Au bonds. Combined ultraviolet photoelectron spectroscopy and DFT data reveal that formation of the 6MP self-assembled monolayer generates a molecular dipole perpendicular to the surface, with negative charges residing at the metal/monolayer interface and positive charges at the monolayer/vacuum interface, which lowers the substrate work function. Scanning tunneling microscopy shows two surface molecular domains: a well-ordered rectangular lattice where molecules are tilted on average 30° with respect to the substrate and aligned 6MP islands where molecules are standing upright. Finally, we found a new electronic state located at -1.7 eV with respect to the Fermi level that corresponds to a localized π molecular state, while the state corresponding to the N-Au bond is hybridized with Au d electrons and stabilized at much lower energies (-3 eV).Instituto de Investigaciones Fisicoquímicas Teóricas y AplicadasConsejo Nacional de Investigaciones Científicas y Técnica

Electronic Structure of a Self-Assembled Monolayer with Two Surface Anchors: 6-Mercaptopurine on Au(111)

The electronic structure of aromatic and aliphatic thiols on Au(111) has been extensively studied in relation to possible applications in molecular electronics. In this work, the effect on the electronic structure of an additional anchor to the S-Au bond using 6-mercaptopurine as a model system has been investigated. Results from X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and density functional theory (DFT) confirm that this molecule adsorbs on Au(111) with S-Au and iminic N-Au bonds. Combined ultraviolet photoelectron spectroscopy and DFT data reveal that formation of the 6MP self-assembled monolayer generates a molecular dipole perpendicular to the surface, with negative charges residing at the metal/monolayer interface and positive charges at the monolayer/vacuum interface, which lowers the substrate work function. Scanning tunneling microscopy shows two surface molecular domains: a well-ordered rectangular lattice where molecules are tilted on average 30° with respect to the substrate and aligned 6MP islands where molecules are standing upright. Finally, we found a new electronic state located at -1.7 eV with respect to the Fermi level that corresponds to a localized π molecular state, while the state corresponding to the N-Au bond is hybridized with Au d electrons and stabilized at much lower energies (-3 eV).Fil: Fernández, Cynthia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Pensa, Evangelina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Carro, Pilar. Universidad de La Laguna; EspañaFil: Salvarezza, Roberto Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Williams, Federico José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Adsorption of Phosphonic-Acid-Functionalized Porphyrin Molecules on TiO2(110)

We studied the adsorption geometry and bonding of mono- and tetraphosphonic-acid-functionalized tetraphenylporphyrin molecules on rutile TiO2(110) surfaces. The investigation was carried out by means of X-ray photoelectron spectroscopy and near edge X-ray absorption fine structure (NEXAFS) measurements. We found that the molecules bind covalently to the surface in a mixed monodentate and bidentate mode implying deprotonation of one or two phosphonate hydroxyl groups. Our NEXAFS data suggest that molecules containing one functional phosphonic acid group are on average tilted further away from the surface than molecules with four functional groups. The highest occupied electronic state of both molecules is in the band gap at 2.1 eV below the Fermi level. Our results demonstrate that the number of functional phosphonic acid groups determine the adsorption geometry of tetraphenylporphyrins.Fil: Fernández, Cynthia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Wechsler, Daniel. Universitat Erlangen-Nuremberg; AlemaniaFil: Rocha, Tulio C. R.. Brazilian Center for Research on Energy and Materials ; BrasilFil: Steinrück, Hans-Peter. Universitat Erlangen-Nuremberg; AlemaniaFil: Lytken, Ole. Universitat Erlangen-Nuremberg; AlemaniaFil: Williams, Federico José. Universitat Erlangen-Nuremberg; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Wet-Chemically Prepared Porphyrin Layers on Rutile TiO2(110)

Porphyrins are large organic molecules that are interesting for different applications, such as photovoltaic cells, gas sensors, or in catalysis. For many of these applications, the interactions between adsorbed molecules and surfaces play a crucial role. Studies of porphyrins on surfaces typically fall into one of two groups: (1) evaporation onto well-defined single-crystal surfaces under well-controlled ultrahigh vacuum conditions or (2) more application-oriented wet chemical deposition onto less well-defined high surface area surfaces under ambient conditions. In this study, we will investigate the wet chemical deposition of 5-(monocarboxyphenyl)-10,15,20-triphenylporphyrin (MCTPP) on well-defined rutile TiO2 (110) single crystals under ambient conditions. Prior to deposition, the TiO2(110) crystals were also cleaned wet-chemically under ambient conditions, meaning none of the preparation steps were done in ultrahigh vacuum. However, after each preparation step, the surfaces were characterized in ultrahigh vacuum with X-ray photoelectron spectroscopy (XPS) and the result was compared with porphyrin layers prepared in ultrahigh vacuum (UHV) by evaporation. The differences of both preparations when exposed to zinc ion solutions will also be discussed.Fil: Wechsler, Daniel. Universitat Erlangen-Nuremberg; AlemaniaFil: Fernández, Cynthia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Köbl, Julia. Universitat Erlangen-Nuremberg; AlemaniaFil: Augustin, Lisa Marie. Universitat Erlangen-Nuremberg; AlemaniaFil: Stumm, Corina. Universitat Erlangen-Nuremberg; AlemaniaFil: Norbert Jux. Universitat Erlangen-Nuremberg; AlemaniaFil: Steinruck, Hans Peter. Universitat Erlangen-Nuremberg; AlemaniaFil: Williams, Federico José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Lytken, Ole. Universitat Erlangen-Nuremberg; Alemani

Plasma β-III tubulin, neurofilament light chain and glial fibrillary acidic protein are associated with neurodegeneration and progression in schizophrenia

Schizophrenia is a progressive disorder characterized by multiple psychotic relapses. After every relapse, patients may not fully recover, and this may lead to a progressive loss of functionality. Pharmacological treatment represents a key factor to minimize the biological, psychological and psychosocial impact of the disorder. The number of relapses and the duration of psychotic episodes induce a potential neuronal damage and subsequently, neurodegenerative processes. Thus, a comparative study was performed, including forty healthy controls and forty-two SZ patients divided into first-episode psychosis (FEP) and chronic SZ (CSZ) subgroups, where the CSZ sub group was subdivided by antipsychotic treatment. In order to measure the potential neuronal damage, plasma levels of β-III tubulin, neurofilament light chain (Nf-L), and glial fibrillary acidic protein (GFAP) were performed. The results revealed that the levels of these proteins were increased in the SZ group compared to the control group (P < 0.05). Moreover, multiple comparison analysis showed highly significant levels of β-III tubulin (P = 0.0002), Nf-L (P = 0.0403) and GFAP (P < 0.015) in the subgroup of CSZ clozapine-treated. In conclusion, β-III tubulin, Nf-L and GFAP proteins may be potential biomarkers of neurodegeneration and progression in SZFundação para a Ciência e a Tecnologia | Ref. SFRH/BD/135623/20Instituto de Salud Carlos III | Ref. P16/00405Ministerio de Sanidad, Igualdad y Política Social | Ref. 2017I054Agencia del Conocimiento en Salud | Ref. PRIS2-17Xunta de Galicia | Ref. IN607C-2017/02Xunta de Galicia | Ref. IN607B 2018/1

Envejecimiento de la población

&bull;Actividades b&aacute;sicas de la vida diaria en personas mayores y factores asociados &bull;Asociaci&oacute;n entre depresi&oacute;n y posesi&oacute;n de mascotas en personas mayores &bull;Calidad de vida en adultos mayores de Santiago aplicando el instrumento WHOQOL-BREF &bull;Calidad de vida en usuarios con enfermedad de Parkinson, demencia y sus cuidadores, comuna de Vitacura &bull;Caracterizaci&oacute;n de egresos hospitalarios de adultos mayores en Puerto Natales (2007-2009) &bull;Comportamiento de las patolog&iacute;as incluidas como GES para el adulto mayor atendido en un Cesfam &bull;Contribuci&oacute;n de vitaminas y minerales a las ingestas recomendadas diarias en ancianos institucionalizados de Madrid &bull;Estado de salud oral del paciente inscrito en el Programa de Visita Domiciliaria &bull;Evaluaci&oacute;n del programa de discapacidad severa en Casablanca con la matriz de marco l&oacute;gico &bull;Factores asociados a satisfacci&oacute;n vital en una cohorte de adultos mayores de Santiago, Chile &bull;Pauta instrumental para la identificaci&oacute;n de riesgos para el adulto mayor autovalente, en su vivienda &bull;Perfil farmacol&oacute;gico del paciente geri&aacute;trico institucionalizado y posibles consecuencias en el deterioro cognitivo &bull;Programa de cuidados paliativos y alivio del dolor en Puerto Natales &bull;Rehabilitaci&oacute;n mandibular implantoprot&eacute;sica: efecto en calidad de vida relacionada con salud bucal en adultos mayores &bull;Salud bucodental en adultos mayores autovalentes de la Regi&oacute;n de Valpara&iacute;so &bull;Transici&oacute;n epidemiol&oacute;gica y el estudio de carga de enfermedad en Brasi

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups

Dispositivos lingüísticos de acogida, aprendizaje expansivo e interculturalidad: Contribuciones para la inclusión educativa de estudiantes extranjeros

Indexación: Scopus.In the context of the progressive increase of foreigners in public schools in Chile and the recent changes in migratory patterns, the presence of students who do not master the working language of the educational system has systematically incremented in recent years. In a scenario marked by the absence of educational policies that respond to this new linguistic diversity, the purpose of our research was to understand how schools have responded to the arrival of foreign students and what educational practices they have implemented to tackle this challenge. Through a two-year school ethnography in four public schools with high enrollment of foreigners, institutional documents were analyzed and field observation, interviews and focus groups were conducted with different actors amidst the educational communities. Through an analysis of thematic content, the results reveal the implementation of ten devices to manage educational responses to foreign students. We have analyzed three of these devices with a focus on linguistics based on the tensions and contradictions that occur within the educational institutions of which they are part, identifying significant elements and dimensions to drive forward expansive learning. Finally, we discuss these findings in light of the advances and challenges of the intercultural approach in our Latin American region.https://www.scielo.br/j/ep/a/NhL67jbv7H7VpZtQYjtHVFt/?lang=e

VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad

Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas. En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región. Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades. En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates. El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento