Alkaline-Silicate REE-HFSE Systems

Development of renewable energy infrastructure requires critical raw materials, such as the rare earth elements (REEs, including scandium) and niobium, and is driving expansion and diversification in their supply chains. Although alternative sources are being explored, the majority of the world’s resources of these elements are found in alkaline-silicate rocks and carbonatites. These magmatic systems also represent major sources of fluorine and phosphorus. Exploration models for critical raw materials are comparatively less well developed than those for major and precious metals, such as iron, copper, and gold, where most of the mineral exploration industry continues to focus. The diversity of lithologic relationships and a complex nomenclature for many alkaline rock types represent further barriers to the exploration and exploitation of REE-high field strength element (HFSE) resources that will facilitate the green revolution. We used a global review of maps, cross sections, and geophysical, geochemical, and petrological observations from alkaline systems to inform our description of the alkaline-silicate REE + HFSE mineral system from continental scale (1,000s km) down to deposit scale (~1 km lateral). Continental-scale targeting criteria include a geodynamic trigger for low-degree mantle melting at high pressure and a mantle source enriched in REEs, volatile elements, and alkalies. At the province and district scales, targeting criteria relate to magmatic-system longevity and the conditions required for extensive fractional crystallization and the residual enrichment of the REEs and HFSEs. A compilation of maps and geophysical data were used to construct an interactive 3-D geologic model (25-km cube) that places mineralization within a depth and horizontal reference frame. It shows typical lithologic relationships surrounding orthomagmatic REE-Nb-Ta-Zr-Hf mineralization in layered agpaitic syenites, roof zone REE-Nb-Ta mineralization, and mineralization of REE-Nb-Zr associated with peralkaline granites and pegmatites. The resulting geologic model is presented together with recommended geophysical and geochemical approaches for exploration targeting, as well as mineral processing and environmental factors pertinent for the development of mineral resources hosted by alkaline-silicate magmatic systems

Los procesos de socialización de docentes de inglés del Programa Nacional de Inglés para educación básica en las primarias públicas de Baja California

El presente estudio busca conocer los procesos de socialización del personal docente que labora en el Programa Nacional de Inglés a nivel primaria y preescolar en Ensenada Baja California, México, para identificar, por un lado, la construcción de la identidad docente desde un enfoque socio pedagógico y; por otro, dar cuenta del contexto en el cual se encuentra inmerso para así contribuir al diálogo en apoyo a acciones que mejoren su entorno. Nuestro propósito no es solo generalizar sobre la construcción de identidades, sino también profundizar sobre el proceso que experimentan docentes que trabajan en el programa. Para enmarcar esta información se realizó un estudio cualitativo con orientación a estudio de caso. Los datos fueron recolectados a través de entrevistas semiestructuradas a un grupo de sujetos clave utilizando el método de análisis por categorías para organizar y concretar los resultados. La intervención circunscribe dos tipos de docentes; aquel grupo que cuenta con una formación pedagógica base, producto de su paso por programas formales de instrucción a nivel de universidad y, otros grupos que obtuvieron su trabajo como docentes por el manejo del inglés o su pertenencia al sistema educativo. También es significativa la manifestación de una falta de inducción al programa para su ingreso al contexto escolar, la precariedad de las condiciones laborales, la falta de apoyo para la capacitación pedagógica y el poco reconocimiento de la imagen del personal docente de lenguas por la sociedad

Attosecond state-resolved carrier motion in quantum materials probed by soft x-ray XANES

Recent developments in attosecond technology led to table-top x-ray spectroscopy in the soft x-ray range, thus uniting the element- and state-specificity of core-level x-ray absorption spectroscopy with the time resolution to follow electronic dynamics in real-time. We describe recent work in attosecond technology and investigations into materials such as Si, SiO2, GaN, Al2O3, Ti, and TiO2, enabled by the convergence of these two capabilities. We showcase the state-of-the-art on isolated attosecond soft x-ray pulses for x-ray absorption near-edge spectroscopy to observe the 3d-state dynamics of the semi-metal TiS2 with attosecond resolution at the Ti L-edge (460 eV). We describe how the element- and state-specificity at the transition metal L-edge of the quantum material allows us to unambiguously identify how and where the optical field influences charge carriers. This precision elucidates that the Ti:3d conduction band states are efficiently photo-doped to a density of 1.9 x 1021 cm 3. The light-field induces coherent motion of intra-band carriers across 38% of the first Brillouin zone. Lastly, we describe the prospects with such unambiguous real-time observation of carrier dynamics in specific bonding or anti-bonding states and speculate that such capability will bring unprecedented opportunities toward an engineered approach for designer materials with pre-defined properties and efficiency. Examples are composites of semiconductors and insulators like Si, Ge, SiO2, GaN, BN, and quantum materials like graphene, transition metal dichalcogens, or high-Tc superconductors like NbN or LaBaCuO. Exiting are prospects to scrutinize canonical questions in multi-body physics, such as whether the electrons or lattice trigger phase transitions

Managing Critical Transition Zones

ABSTRACT Ecosystems that function as critical transition zones (CTZs) among terrestrial, freshwater, and marine habitats are closely connected to the ecosystems adjacent to them and are characterized by a rapid flux of materials and organisms. CTZs play various roles, including mediating water flows, accumulating sediments and organic matter, processing nutrients, and providing opportunities for recreation. They are particularly difficult to manage because they tend to be small, albeit important, components of large watersheds, and managers may not have control over the entire landscape. Moreover, they are often the focus of intensive human activity. Consequently, CTZs are critically important zones, and their preservation and protection are likely to require unique collaboration among scientists, managers, and stakeholders. Scientists can learn a great deal from the study of these ecosystems, taking advantage of small size and the importance of fluxes, but a good understanding of adaptive management strategies is needed to establish a dialogue with managers and stakeholders on technical and management issues. An understanding of risk analysis is also important to help set meaningful goals and establish logical strategies that include all of the interested parties. Successful restoration of a CTZ is the best test of the quality of knowledge about its structure and function. Much has already been learned about coastal CTZs through restoration projects, and the large number of such projects involving riparian CTZs in particular suggests that there is considerable opportunity for fruitful collaborations between scientists and managers

Antarctic ecosystems in transition – life between stresses and opportunities

Important findings from the second decade of the 21st century on the impact of environmental change on biological processes in the Antarctic were synthesised by 26 international experts. Ten key messages emerged that have stakeholder-relevance and/or a high impact for the scientific community. They address (i) altered biogeochemical cycles, (ii) ocean acidification, (iii) climate change hotspots, (iv) unexpected dynamism in seabed-dwelling populations, (v) spatial range shifts, (vi) adaptation and thermal resilience, (vii) sea ice related biological fluctuations, (viii) pollution, (ix) endangered terrestrial endemism and (x) the discovery of unknown habitats. Most Antarctic biotas are exposed to multiple stresses and considered vulnerable to environmental change due to narrow tolerance ranges, rapid change, projected circumpolar impacts, low potential for timely genetic adaptation, and migration barriers. Important ecosystem functions, such as primary production and energy transfer between trophic levels, have already changed, and biodiversity patterns have shifted. A confidence assessment of the degree of 'scientific understanding' revealed an intermediate level for most of the more detailed sub-messages, indicating that process-oriented research has been successful in the past decade. Additional efforts are necessary, however, to achieve the level of robustness in scientific knowledge that is required to inform protection measures of the unique Antarctic terrestrial and marine ecosystems, and their contributions to global biodiversity and ecosystem services

Elaboración de papel ecológico a partir de fibras vegetales para uso artístico

El propósito de este proyecto de investigación es la elaboración de papel ecológico a partir de la experimentación con diversas fibras vegetales de la provincia de Misiones para ser utilizado en el campo de las artes plásticas. Pretende optimizar los recursos humanos existentes, a través de la conformación de un equipo interdisciplinario que aúne conocimientos científico-tecnológicos y artísticos, sistematizar el proceso de producción del papel, ampliar su gama de posibilidades cromáticas utilizando vegetales de la zona y fomentar la elaboración de papel como soporte y medio de expresión artística. La metodología aplicada en el desarrollo del proyecto consta de dos etapas, una heurística y otra hermenéutica. (Párrafo extraído del texto a modo de resumen) Facultad de Bellas Arte

Alkaline-Silicate REE-HFSE Systems

Development of renewable energy infrastructure requires critical raw materials, such as the rare earth elements (REEs, including scandium) and niobium, and is driving expansion and diversification in their supply chains. Although alternative sources are being explored, the majority of the world’s resources of these elements are found in alkaline-silicate rocks and carbonatites. These magmatic systems also represent major sources of fluorine and phosphorus. Exploration models for critical raw materials are comparatively less well developed than those for major and precious metals, such as iron, copper, and gold, where most of the mineral exploration industry continues to focus. The diversity of lithologic relationships and a complex nomenclature for many alkaline rock types represent further barriers to the exploration and exploitation of REE-high field strength element (HFSE) resources that will facilitate the green revolution. We used a global review of maps, cross sections, and geophysical, geochemical, and petrological observations from alkaline systems to inform our description of the alkaline-silicate REE + HFSE mineral system from continental scale (1,000s km) down to deposit scale (~1 km lateral). Continental-scale targeting criteria include a geodynamic trigger for low-degree mantle melting at high pressure and a mantle source enriched in REEs, volatile elements, and alkalies. At the province and district scales, targeting criteria relate to magmatic-system longevity and the conditions required for extensive fractional crystallization and the residual enrichment of the REEs and HFSEs. A compilation of maps and geophysical data were used to construct an interactive 3-D geologic model (25-km cube) that places mineralization within a depth and horizontal reference frame. It shows typical lithologic relationships surrounding orthomagmatic REE-Nb-Ta-Zr-Hf mineralization in layered agpaitic syenites, roof zone REE-Nb-Ta mineralization, and mineralization of REE-Nb-Zr associated with peralkaline granites and pegmatites. The resulting geologic model is presented together with recommended geophysical and geochemical approaches for exploration targeting, as well as mineral processing and environmental factors pertinent for the development of mineral resources hosted by alkaline-silicate magmatic systems

Elaboración de papel ecológico a partir de fibras vegetales para uso artístico

El propósito de este proyecto de investigación es la elaboración de papel ecológico a partir de la experimentación con diversas fibras vegetales de la provincia de Misiones para ser utilizado en el campo de las artes plásticas. Pretende optimizar los recursos humanos existentes, a través de la conformación de un equipo interdisciplinario que aúne conocimientos científico-tecnológicos y artísticos, sistematizar el proceso de producción del papel, ampliar su gama de posibilidades cromáticas utilizando vegetales de la zona y fomentar la elaboración de papel como soporte y medio de expresión artística. La metodología aplicada en el desarrollo del proyecto consta de dos etapas, una heurística y otra hermenéutica. (Párrafo extraído del texto a modo de resumen) Facultad de Bellas Arte

Elaboración de papel ecológico a partir de fibras vegetales para uso artístico

El propósito de este proyecto de investigación es la elaboración de papel ecológico a partir de la experimentación con diversas fibras vegetales de la provincia de Misiones para ser utilizado en el campo de las artes plásticas. Pretende optimizar los recursos humanos existentes, a través de la conformación de un equipo interdisciplinario que aúne conocimientos científico-tecnológicos y artísticos, sistematizar el proceso de producción del papel, ampliar su gama de posibilidades cromáticas utilizando vegetales de la zona y fomentar la elaboración de papel como soporte y medio de expresión artística. La metodología aplicada en el desarrollo del proyecto consta de dos etapas, una heurística y otra hermenéutica. (Párrafo extraído del texto a modo de resumen) Facultad de Bellas Arte