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O artigo analisa o Plano Municipal de Cultura (PMC) do município de Itabirito, em Minas Gerais, enquanto coadjuvante para o desenvolvimento de políticas públicas no setor cultural nos últimos anos (2016-2020). Como desenvolvimento metodológico, é abordado como os Planos Municipais de Cultura atuam no fortalecimento das políticas públicas para o desenvolvimento da cultura, assim como na preservação do Patrimônio Cultural. Entende-se que os planos de cultura são as “engrenagens” que fazem funcionar o sistema cultural, sem os quais esse motor não funciona, não gira e o sistema não “anda”. Conclui-se que o Plano Municipal de Cultura de Itabirito é um documento participativo, técnico e planejado que busca alinhar os anseios da população aos interesses e possibilidades do Poder Público local.

Este artículo analiza el proceso de implementación de un proyecto turístico en la comuna italiana de Santo Stefano di Sessanio, entre 1999 y 2014. Tras un contexto de estancamiento económico y declive demográfico emergidos a finales del siglo XIX, la localidad ha venido experimentando desde principios del siglo XX un conjunto de intervenciones turísticas que buscan evocar la historicidad local a partir de la instrumentalización de los aspectos morfológicos de su paisaje cultural. Eso ha culminado en el restauro de un conjunto de edificios con el fin de transformarles en una red de albergues difusos. El artículo está armado tras un recorrido teórico que incluye análisis de materiales brindados por instituciones locales y grupos privados que han intervenido en dicha comuna. De este modo, el trabajo evidencia la importancia que el turismo ha tenido en el municipio de Santo Stefano di Sessanio post el contexto de abandono territorial.

One of the most promising routes for achieving high critical currents in superconductors is to incorporate dispersed, non-superconducting nanoparticles to control the dissipative motion of vortices. However, these inclusions reduce the overall superconducting volume and can strain the interlaying superconducting matrix, which can detrimentally reduce Tc. Consequently, an optimal balance must be achieved between the nanoparticle density np and size d. Determining this balance requires garnering a better understanding of vortex–nanoparticle interactions, described by strong pinning theory. Here, we map the dependence of the critical current on nanoparticle size and density in (Y0.77, Gd0.23)Ba2Cu3O7−δ films in magnetic fields of up to 35 T and compare the trends to recent results from time-dependent Ginzburg–Landau simulations. We identify consistency between the field-dependent critical current Jc(B) and expectations from strong pinning theory. Specifically, we find that Jc ∝ B−α, where α decreases from 0.66 to 0.2 with increasing density of nanoparticles and increases roughly linearly with nanoparticle size d/ξ (normalized to the coherence length). At high fields, the critical current decays faster (∼B−1), suggesting that each nanoparticle has captured a vortex. When nanoparticles capture more than one vortex, a small, high-field peak is expected in Jc(B). Due to a spread in defect sizes, this novel peak effect remains unresolved here. Finally, we reveal that the dependence of the vortex creep rate S on nanoparticle size and density roughly mirrors that of α, and we compare our results to low-T nonlinearities in S(T) that are predicted by strong pinning theory.

O conceito de paisagem cultural, historicamente associado à ciência geográfica, foi interpretado como uma tipologia do Patrimônio Mundial e incorporado pelo Comitê da UNESCO em 1992. O artigo objetiva a compreensão deste conceito e das tipologias dele derivadas e operadas pela UNESCO, nos dois casos ocorridos no Brasil: “Rio de Janeiro: paisagens cariocas entre o mar e a montanha” e “Conjunto Moderno da Pampulha”. Após a análise dos dossiês de candidatura ao título de Patrimônio Mundial foi possível identificar os usos da memória e as construções narrativas derivados da confluência do conceito de paisagem cultural e das políticas públicas dos campos do patrimônio brasileiro e mundial. O resultado são os discursos que consagraram esses dois sítios brasileiros como paisagens culturais excepcionais, mundialmente reconhecidas.

Abstract Metamagnetism occuring inside a ferromagnetic phase is peculiar. Therefore, Sr4Ru3O10, a T C = 105 K ferromagnet, has attracted much attention in recent years, because it develops a pronounced metamagnetic anomaly below T C for magnetic fields applied in the crystallographic ab-plane. The metamagnetic transition moves to higher fields for lower temperatures and splits into a double anomaly at critical fields H c1 = 2.3 T and H c2 = 2.8 T, respectively. Here, we report a detailed study of the different components of the magnetization vector as a function of temperature, applied magnetic field, and varying angle in Sr4Ru3O10. We discover for the first time a reduction of the magnetic moment in the plane of rotation at the metamagnetic transition. The anomaly shifts to higher fields by rotating the field from H ⊥ c to H || c. We compare our experimental findings with numerical simulations based on spin reorientation models taking into account magnetocrystalline anisotropy, Zeeman effect and antisymmetric exchange interactions. While Magnetocrystalline anisotropy combined with a Zeeman term are sufficient to explain a metamagnetic transition in Sr4Ru3O10, a Dzyaloshinskii-Moriya term is crucial to account for the reduction of the magnetic moment as observed in the experiments.

Abstract Room‐temperature magnetoelectric (ME) coupling is developed in artificial multilayers and nanocomposites composed of magnetostrictive and electrostrictive materials. While the coupling mechanisms and strengths in multilayers are widely studied, they are largely unexplored in vertically aligned nanocomposites (VANs), even though theory has predicted that VANs exhibit much larger ME coupling coefficients than multilayer structures. Here, strong transverse and longitudinal ME coupling in epitaxial BaTiO3:CoFe2O4 VANs measured by both optical second harmonic generation and piezoresponse force microscopy under magnetic fields is reported. Phase field simulations have shown that the ME coupling strength strongly depends on the vertical interfacial area which is ultimately controlled by pillar size. The ME coupling in VANs is determined by the competition between the vertical interface coupling effect and the bulk volume conservation effect. The revealed mechanisms shed light on the physical insights of vertical interface coupling in VANs in general, which can be applied to a variety of nanocomposites with different functionalities beyond the studied ME coupling effect.

Many second phase additions to YBa2Cu3O7−x (YBCO) films, in particular those that self-assemble into aligned nanorod and nanoparticle structures, enhance performance in self and applied fields. Of particular interest for additions are Ba-containing perovskites that are compatible with YBCO. In this report, we discuss the addition of Ba2YRuO6 to bulk and thick-film YBCO. Sub-micron, randomly oriented particles of this phase were found to form around grain boundaries and within YBCO grains in bulk sintered pellets. Within the limits of EDS, no Ru substitution into the YBCO was observed. Thick YBCO films were grown by pulsed laser deposition from a target consisting of YBa2Cu3Oy with 5 and 2.5 mole percent additions of Ba2YRuO6 and Y2O3, respectively. Films with enhanced in-field performance contained aligned, self-assembled Ba2YRuO6 nanorods and strained Y2O3 nanoparticle layers. A 0.9 µm thick film was found to have a self-field critical current density (Jc) of 5.1 MA/cm2 with minimum Jc(Q, H=1T) of 0.75 MA/cm2. Conversely, Jc characteristics were similar to YBCO films without additions when these secondary phases formed as large, disordered phases within the film. A 2.3 µm thick film with such a distribution of secondary phases was found to have reduced self-field Jc values of 3.4 MA/cm2 at 75.5 K and Jc(min, Q, 1T) of 0.4 MA/cm2.

Biaxially textured SmxZr1-x Oy (SZO) thin films have been grown directly on. an ion beam assisted deposited (IBAD) MgO template, without using an intermediate homoepitaxial MgO layer. SZO buffer layers were deposited using reactive magnetron sputtering of a Sm (50 at.%)-Zr (50 at.%) alloy target. The SZO texture is similar to that of the MgO template. Epitaxial YBCO films, ∼ 1 μm-thick, grown by pulsed laser deposition on SZO buffered coated conductors have high critical current densities. The in-field measurements indicate that superconducting samples with SZO as buffer are as good as STO/homoepitaxial MgO buffered samples. These results demonstrate that SZO is an appropriate buffer for the fabrication of low cost YBCO/IBAD MgO coated conductors with excellent transport properties. [ABSTRACT FROM AUTHOR]

We explore the interplay between the mass anisotropy and the uniaxial pinning of tilted columnar defects (CD) in a YBa2Cu3O7 single crystal. At high temperatures T and fields H a sharp peak in the irreversible magnetization Mi at the direction of the tracks signals the presence of the CD. At low T such a peak is not observed, and the influence of the CD appears only as a perturbation to the angular dependence due to the anisotropy. We show that at low T and high H the uniaxial effects due to CD can be recovered by performing an anisotropic rescaling. As expected, this scaling fails at low H. [ABSTRACT FROM AUTHOR]

Ultrathin epitaxial superconducting NbN (18 nm) films, exhibiting a superconducting transition temperature of 14 K and a critical current density as high as 5.2 MA cm−2at 5 K under zero magnetic field, were grown on SrTiO3(STO) by a chemical solution technique, polymer assisted deposition (PAD). [ABSTRACT FROM AUTHOR]