Suchergebnisse

This dissertation examines the cycling-friendly policies and infrastructure of Auckland, Buenos Aires, and Copenhagen as well as additional transport policies that might influence cycling. The final goal of this examination is to extract some lessons from the capital cities of Argentina and Denmark in order to make suggestions on how Auckland can become a more bicycle-friendly city. The literature has found that these 3 cities find themselves in 3 different stages of development in regard to their cycling policies. Auckland's cycling policies are more rudimentary than its counterparts, Buenos Aires cycling policies are developing and have made remarkable improvements, and Copenhagen's are highly proficient and regarded as world leaders. The keys to achieving high rates of cycling in Buenos Aires and Copenhagen seem to be the provision of separated cycle tracks, retrofitting of intersections to increase safety, efficient bike share schemes, sufficient secure parking, and campaigns to encourage cycling. The most effective way of introducing similar pro-bike policies and infrastructure in Auckland would be to consider Buenos Aires as a medium term model and Copenhagen as a long term model. In consequence, Auckland should try to adopt Buenos Aires' policies first and once they have produced positive results, move on to replicate Copenhagen's more developed policies. Finally, a variable that was out of the scope of this research but is determinant to produce these desired changes is strong political willingness. Buenos Aires' and Copenhagen's authorities have shown sound political determination in supporting transport policies that usually sparked opposition and backlash. Without a clear determination, pro-bike policies will not produce the expected results, no matter how well developed they are.

Comprendo que el Sr. General D. Eloy Alfaro, Presidente de la República, someterá á la decisión del Congreso de 1899, los últimos arreglos con los Tenedores de bonos de la Deuda Anglo-ecuatoriana. Por patriotismo estoy, pues, obligado á expresar mis ideas y apreciaciones sobre esta nueva conversión, desde luego que mis estudios y publicaciones sobre una materia que, por su aridez, no interesa á todos, me dan derecho á ser oído por los miembros de la actual Legislatura; con mucho mayor razón que mi extenso "Informe sobre la Deuda Externa" fué dado á la luz, en 1896, por contrato con el Ministro de Hacienda; y, en cierta manera, debo complementar ese trabajo, contribuyendo, á medida de mis facultades, á la salvación económica de la República, mediante un arreglo equitativo, conveniente y posible para los medios rentísticos con los cuales cuenta el Estado para el pago de tan ingente deuda.

La recepción de la obra de Park se ha ceñido principalmente a sus trabajos de ecología urbana. Hoy día se advierte una lectura más amplia y plural que explora entre otros aspectos sus aportaciones teóricas y empíricas a otros campos de interés como la opinión pública y la prensa. El artículo aborda la vinculación existente entre prensa y ciudad, laboratorios de la modernidad y espacios de socialización, en el pensamiento de Park, partiendo de su experiencia como reporter y su vocación académica.

Siguiendo el texto clásico de Federico Nietzsche, Así hablaba Zaratustra, en el artículo se dice que Zaratustra continuamente regresa a los niveles transhistóricos que la soledad de las montañas le permite manejar. Necesita clarificar el constante aprendizaje de que es objeto el mundo subhistórico, para tener acceso a la creatividad que pregona. Llega a concluir la negatividad de cualquier tipo de misericordia: el innovador no puede ser misericordioso en la medida en que el amor que implica su creatividad va más allá de toda piedad; la creación destruye irremisiblemente lo previamente instaurado, con mayor razón si esto es débil.

Due to their outstanding electronic and mechanical properties, single-walled carbon nanotubes (SWCNTs) are promising nanomaterials for the future generation of optoelectronic devices and composites. However, their scarce solubility limits their application in many technologies that demand solution-processing of high-purity SWCNT samples. Although some non-covalent functionalization approaches have demonstrated their utility in extracting SWCNTs into different media, many of them produce short-lived dispersions or ultimately suffer from contamination by the dispersing agent. Here, we introduce an unprecedented strategy that relies on a cooperative clamping process. When mixing (6,5)SWCNTs with a dinucleoside monomer that is able to self-assemble in nanorings via Watson-Crick base-pairing, a synergistic relationship is established. On one hand, the H-bonded rings are able to associate intimately with SWCNTs by embracing the tube sidewalls, which allows for an efficient SWCNT debundling and for the production of long-lasting SWCNT dispersions of high optical quality along a broad concentration range. On the other, nanoring stability is enhanced in the presence of SWCNTs, which are suitable guests for the ring cavity and contribute to the establishment of multiple cooperative noncovalent interactions. The inhibition of these reversible interactions, by just adding, for instance, a competing solvent for hydrogen-bonding, proved to be a simple and effective method to recover the pristine nanomaterial with no trace of the dispersing agent. ; Funding from the European Union (ERC-Starting Grants: 279548 (DGR) and 307609 (EMP)), MINECO (Grants: CTQ2014- 57729-P (DGR) and CTQ2014-60541-P (EMP), FPU13/03371 (LdJ), JdC-2015-23531 postdoctoral fellowship (BNO)) and the Comunidad de Madrid (Grant: MAD2D-CM program S2013/ MIT-3007 (EMP)) is gratefully acknowledged. IMDEA Nanociencia acknowledges support from the 'Severo Ochoa' Programme for Centres of Excellence in R&D (MINECO, Grant SEV- 2016-0686).

El trabajo de investigación se realizó con el objetivo de diagnosticar la situación urbanística de la ciudad de Huánuco a fin de determinar la sostenibilidad del funcionamiento de la Escuela Académico Profesional de arquitectura en la Universidad Nacional Hermilio Valdizán. Para lo cual se diseñó un estudio de tipo aplicado en el nivel descriptivo; se realizaron análisis sobre las condiciones arquitectónicas de la ciudad de Huánuco, por medio de las opiniones de los actores sociales involucrados en temas de formulación de políticas públicas y ciudadanos comunes conformantes de una muestra de 149 personas; además, se analizó material bibliográfico referente. Las técnicas usadas para la recolección de la data fueron: la encuesta formulada en base a una escala valorativa de Likert; al mismo tiempo se realizaron entrevistas y análisis a las listas de cotejo del cual se obtuvieron los siguientes resultados: el 85% de la población huanuqueña considera que a pesar de existir un Plan Director, éste no ha sido operativo ya que no ha permitido controlar el crecimiento urbano desordenado en cuanto al sistema vial; usos del suelo y equipamiento urbano, se halló también que el 95% de los locales destinados para uso público no cuentan con una infraestructura que se adecuen a las normas de accesibilidad para personas discapacitadas, el 85% de las personas opinan que es necesaria la intervención y participación de profesionales en arquitectura en la elaboración de proyectos y gestión de desarrollo urbano ligados a la construcción de todo tipo de obras. Se concluye que existe la necesidad de formar profesionales en el campo de la arquitectura y urbanismo, a fin de que estos aporten al desarrollo urbanístico, social e integral de la Región. ; The research work was carried out with the aim of diagnosing the urban situation of the city of Huánuco, in order to determine the sustaining of the Professional Academic School of architecture at Hermilio Valdizán Public University. It was designed a study of type applied in the descriptive level; analyses were carried out on the architectural conditions of the city of Huánuco, through opinions of the social actors involved in topics of formulation of political public and citizens common of a sample formed of 149 persons, so then the bibliographical material in reference also was analyzed. The techniques used for gathering data were: the survey was formulated according to the scale of Likert; it was carried out interviews and analyze to the lists of collation and the obtained results were: 85% of the population from Huánuco, consider that in spite of existing a Master Plan, nevertheless, this one has not been operative since it has not allowed to control the disorderly Urban growth, as far as the Road System; Uses of the ground and Urban Equipment, it also was found that 95% of the premises destined, for uses public, do not count on an infrastructure that are adapted to the norms of accessibility for disabled people, 85% of the people think that it is necessary the intervention and participation of professionals in architecture in the elaboration of projects and Management of Urban Development, linked to the construction of all kind of works. It was concludes that the necessity exists to train professionals in the field of the architecture and Urbanism, in order that these professionals contribute to the urban development, social and integral of the Region.

The fabrication of van der Waals heterostructures, artificial materials assembled by individual stacking of 2D layers, is among the most promising directions in 2D materials research. Until now, the most widespread approach to stack 2D layers relies on deterministic placement methods, which are cumbersome and tend to suffer from poor control over the lattice orientations and the presence of unwanted interlayer adsorbates. Here, we present a different approach to fabricate ultrathin heterostructures by exfoliation of bulk franckeite which is a naturally occurring and air stable van der Waals heterostructure (composed of alternating SnS 2-like and PbS-like layers stacked on top of each other). Presenting both an attractive narrow bandgap (<0.7 eV) and p-type doping, we find that the material can be exfoliated both mechanically and chemically down to few-layer thicknesses. We present extensive theoretical and experimental characterizations of the material's electronic properties and crystal structure, and explore applications for near-infrared photodetectors ; A.C.-G. acknowledges financial support from the BBVA Foundation through the fellowship 'I Convocatoria de Ayudas Fundacion BBVA a Investigadores, Innovadores y Creadores Culturales' ('Semiconductores ultradelgados: hacia la optpelectronica flexible'), from the MINECO (Ramón y Cajal 2014 program, RYC-2014-01406), from the MICINN (MAT2014-58399-JIN) and from European Commission under the Graphene Flagship, contract CNECTICT-604391. E.M.P. acknowledges financial support from the European Research Council (MINT, ERC-StG-307609) and from the MINECO of Spain (CTQ2014-60541-P). E.G. gratefully acknowledges the AMAROUT II fellowship program for receiving a grant for transnational mobility (Marie Curie Action, FP7-PEOPLE- 2011-COFUND (291803)). A.J.M.-M., G.R.-B. and N.A. acknowledge the support of the MICCINN/MINECO (Spain) through the programmes MAT2014-57915-R, BES-2012-057346 and FIS2011-23488 and Comunidad de Madrid (Spain) through the programme S2013/MIT-3007 (MAD2D). J.O.I. and H.S.J.v.d.Z. acknowledge the support of the Dutch organization for Fundamental Research on Matter (FOM) and by the Ministry of Education, Culture, and Science (OCW). M.A.N. acknowledeges the support of the MICCINN/MINECO (Spain) through the programmes MAT2013-49893-EXP and MAT2014-59315-R. Authors M.A.N., A.J.M.-M. and A.C.-G. acknowledge the support from ALBA Synchrotron for the experiments performed at Circe beamline (BL24-CIRCE) at ALBA Synchrotron with the collaboration of ALBA staff (proposal ID 2015091399). W.S.P. acknowledges CAPES Foundation, Ministry of Education of Brazil, under grant BEX 9476/13-0. W.S.P. and J.J.P. acknowledge MICCINN/MINECO (Spain) for financial support under grant FIS2013-47328-C02-1; the European Union structural funds and the Comunidad de Madrid MAD2D-CM programme under grant nos. P2013/MIT-3007 and P2013/MIT-2850; the Generalitat Valenciana under grant no. PROMETEO/2012/011

Context. The Centaur (10199) Chariklo has the first ring system discovered around a small object. It was first observed using stellar occultation in 2013. Stellar occultations allow sizes and shapes to be determined with kilometre accuracy, and provide the characteristics of the occulting object and its vicinity. Aims. Using stellar occultations observed between 2017 and 2020, our aim is to constrain the physical parameters of Chariklo and its rings. We also determine the structure of the rings, and obtain precise astrometrical positions of Chariklo. Methods. We predicted and organised several observational campaigns of stellar occultations by Chariklo. Occultation light curves were measured from the datasets, from which ingress and egress times, and the ring widths and opacity values were obtained. These measurements, combined with results from previous works, allow us to obtain significant constraints on Chariklo's shape and ring structure. Results. We characterise Chariklo's ring system (C1R and C2R), and obtain radii and pole orientations that are consistent with, but more accurate than, results from previous occultations. We confirm the detection of W-shaped structures within C1R and an evident variation in radial width. The observed width ranges between 4.8 and 9.1 km with a mean value of 6.5 km. One dual observation (visible and red) does not reveal any differences in the C1R opacity profiles, indicating a ring particle size larger than a few microns. The C1R ring eccentricity is found to be smaller than 0.022 (3 sigma), and its width variations may indicate an eccentricity higher than similar to 0.005. We fit a tri-axial shape to Chariklo's detections over 11 occultations, and determine that Chariklo is consistent with an ellipsoid with semi-axes of 143.8(-1.5)(+1.4), 135.2(-2.8)(+1.4), and 99.1(-2.7)(+5.4) km. Ultimately, we provided seven astrometric positions at a milliarcsecond accuracy level, based on Gaia EDR3, and use it to improve Chariklo's ephemeris. ; European Research Council under the European Community's H2020 669416 Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) Fundacao de Apoio a Pesquisa do Distrito Federal (FAPDF) 465376/2014-2 European Union H2020-MSCA-ITN-2019 860470 Novo Nordisk Foundation Interdisciplinary Synergy Programme NNF19OC0057374 Fonds de la Recherche Scientifique - FNRS PDR T.0120.21 Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ) BEM 150612/2020-6 FB-R 314772/2020-0 RV-M 304544/2017-f5 401903/2016-8 JIBC 308150/2016-3 305917/20196 MA 427700/2018-3 ; Versión aceptada para publicar - Postprint

We present a search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors. For this search, ephemerides overlapping the run period were obtained for all pulsars using radio and X-ray observations. We demonstrate an updated search method that allows for small uncertainties in the pulsar phase parameters to be included in the search. We report no signal detection from any of the targets and therefore interpret our results as upper limits on the gravitational wave signal strength. The most interesting limits are those for young pulsars. We present updated limits on gravitational radiation from the Crab pulsar, where the measured limit is now a factor of 7 below the spin-down limit. This limits the power radiated via gravitational waves to be less than similar to 2% of the available spin-down power. For the X-ray pulsar J0537-6910 we reach the spin-down limit under the assumption that any gravitational wave signal from it stays phase locked to the X-ray pulses over timing glitches, and for pulsars J1913+1011 and J1952+3252 we are only a factor of a few above the spin-down limit. Of the recycled millisecond pulsars, several of themeasured upper limits are only about an order of magnitude above their spin-down limits. For these our best (lowest) upper limit on gravitational wave amplitude is 2.3 x 10(-26) for J1603-7202 and our best (lowest) limit on the inferred pulsar ellipticity is 7.0 x 10(-8) for J2124-3358. ; Australian Research Council ; Council of Scientific and Industrial Research of India ; Istituto Nazionale di Fisica Nucleare of Italy ; Spanish Ministerio de Educacion y Ciencia ; Conselleria d'Economia Hisenda i Innovacio of the Govern de les Illes Balears ; Netherlands Organisation for Scientific Research ; Royal Society ; Scottish Funding Council ; Polish Ministry of Science and Higher Education ; Foundation for Polish Science ; Scottish Universities Physics Alliance ; National Aeronautics and Space Administration ; Carnegie Trust ; Leverhulme Trust ; David and Lucile Packard Foundation ; Research Corporation ; Alfred P. Sloan Foundation ; Natural Sciences and Engineering Research Council of Canada ; Commonwealth Government ; Astronomy