842 research outputs found
Health in my community: Conducting and evaluating photovoice as a tool to promote environmental health and leadership among Latino/a youth
BackgroundThe PhotoVoice method has shown substantial promise for work with youth in metropolitan areas, yet its potential for use with Latino youth from agricultural areas has not been well documented.ObjectivesThis project was designed to teach environmental health to 15 high school youth while building their individual and community capacity for studying and addressing shared environmental concerns. The project also aimed to test the utility of PhotoVoice with Latino agricultural youth.MethodsFifteen members of the Youth Community Council (YCC), part of a 15-year project with farmworker families in Salinas, CA, took part in a 12-week PhotoVoice project. Their pictures captured the assets and strengths of their community related to environmental health, and were then analyzed by participants. A multi-pronged evaluation was conducted.ResultsYCC members identified concerns such as poor access to affordable, healthy foods and lack of safe physical spaces in which to play, as well as assets, including caring adults and organizations, and open spaces in surrounding areas. Participants presented their findings on radio, television, at local community events, and to key policy makers. The youth also developed two action plans, a successful 5K run/walk and a school recycling project, still in progress. Evaluation results included significant changes in such areas as perceived ability to make presentations, leadership, and self-confidence, as well as challenges including transportation, group dynamics, and gaining access to people in power.ConclusionThe PhotoVoice method shows promise for environmental health education and youth development in farmworker communities
The semantic effects of verb raising and its consequences in second language grammars
This article considers whether highly proficient second language speakers of English can distinguish meaning contrasts associated with constructions where there is a raising be, and constructions where there is a non-raising thematic verb, as illustrated in the difference between (1a) and (1b): 1a. Kim is reading a novel (`event-in-progress/existential ? interpretation
Physiological requirements for carbonate precipitation during biofilm development of Bacillus subtilis etfA mutant
Although the implications of calcium carbonate (CaCO(3)) precipitation by microorganisms in natural environments are quite relevant, the physiology and genetics of this phenomenon are poorly understood. We have chosen Bacillus subtilis 168 as our model to study which physiological aspects are associated with CaCO(3) (calcite) formation during biofilm development when grown on precipitation medium. A B. subtilis eftA mutant named FBC5 impaired in calcite precipitation was used for comparative studies. Our results demonstrate that inactivation of etfA causes a decrease in the pH of the precipitation medium during biofilm development. Further analysis demonstrated that eftA extrudes an excess of 0.7 mol H(+) L(-1) with respect to B. subtilis 168 strain. Using media buffered at different pH values, we were able to control calcite formation. Because etfA encodes the alpha-subunit of a putative flavoprotein involved in fatty acid metabolism, we compared the intracellular levels of NADH among strains. Our physiological assay showed that FBC5 accumulated up to 32 times more NADH than the wild-type strain. We propose that the accumulation of NADH causes a deregulation in the generation of the proton motive force (DeltamicroH(+)) in FBC5 producing the acidification
Structure and evolution of the Jandía Miocene Volcanic Edifice (Fuerteventura, Canary Islands)
El Edificio Volcánico Mioceno de Jandía constituye un gran edificio central formado a través de diferentes ciclos de construcción
volcánica y destrucción en forma de grandes deslizamientos gravitacionales. En este sentido, al menos 3 grandes deslizamientos gravitacionales han afectado al Edificio Volcánico Mioceno de Jandía
a lo largo de su historia; el del Morro de Mungía, que destruyó el
flanco sur del Edificio de Jandía Superior Oriental; el de La Degollada
de Cofete que afectó, posteriormente, a todo el sector occidental
de este mismo edificio y, sobre cuyos depósitos de avalancha rocosa creció el Edificio de Jandía Superior Occidental; y, por último, el
deslizamiento, que, posteriormente afectó al flanco septentrional de
todo el Edificio Superior de Jandía, responsable de la formación del
actual arco de Cofete. Existe, además, la posibilidad de que el Edificio
Inferior de Jandía sufriera un temprano deslizamiento gravitacional
de su flanco Norte, dando lugar a una fuerte depresión abierta al
Norte sobre la que creció posteriormente el Edificio de Jandía Medio
y el Edificio de Jandía Superior OrientalThe Miocene volcanic Edifice of Jandía is a large central volcano
formed through different cycles of volcanic construction and destruction by large gravitational landslides. In this sense, at least three large
gravitational landslides affected the Miocene volcanic Edifice of Jandía: the Morro de Mungía landslide, which destroyed the southern
flank of the Upper East Jandía Edifice; La Degollada de Cofete landslide, that subsequently affected the entire western sector of this same
Edifice and on whose rocky avalanche deposits the Western Upper
Jandía Edifice grew; and finally, a last landslide which afterwards
affected the northern flank of the entire Jandía Edifice, giving rise to
the formation of the current Cofete arch. It is also possible that the
Lower Jandía Edifice underwent an early gravitational landslide of its
northern flank, which resulted in the formation of a large depression
open to the North, on top of which the Middle Jandía Edifice and the
Upper East Jandía Edifice gre
The end of the demographic dividend in Latin America: challenges for economic and social policies
Artículo de revistaPopulation ageing is a major global challenge. The Latin American economies have a younger population structure than other emerging and advanced economies, which has allowed them to enjoy the so-called demographic dividend (a favourable working age/non-working age population ratio). However, according to the latest demographic projections of the United Nations (UN), it is estimated that in 2020 the Latin American population pyramid will resemble that of the advanced economies in 1990 and that, by around 2050, both groups will have similar population profiles. This article documents the current demographic trends in Latin America and discusses the main related challenges, in particular, those arising from the adaptation of social welfare systems to population ageing
Hexagonal Boron Nitride Nanosheets Grown via Chemical Vapor Deposition for Silver Protection
© 2019 American Chemical Society. In this study, hexagonal boron nitride nanosheets (h-BNNS) have been grown on polycrystalline silver substrates via chemical vapor deposition (CVD) using ammonia borane as a precursor. The h-BNNS are of few-atomic-layer thickness and form continuous coverage over the whole Ag substrate. The atomically thin coating poses negligible interference to the reflectivity in the UV-visible range. The nanosheet coating also proves very effective in protecting Ag foil chemically. In contrast to bare Ag foil, the coated foil displayed only minor decolorization under high concentration of H2S. The study indicates that h-BNNS can be a promising protective coating for Ag based items such as jewelry or mirrors used in astronomical telescopes
Gestionar la construcción de la metodología axiológica para la formación en valores en el Colegio Jalisco
Trabajo que presenta la intervención realizada en el Colegio Jalisco, la cual tuvo el objetivo de construir una metodología institucional a través del trabajo colegiado para generar espacios de reflexión sobre la práctica docente. Se buscó el análisis por parte de directivos y docentes de las prácticas pedagógicas existentes en la institución y de la teoría axiológica para promover la apropiación de conocimientos nuevos en relación a la formación en valores, la formación docente y el perfil de egreso del alumno
Machine-learning potentials for nanoscale simulations of deformation and fracture: example of TiB ceramic
Machine-learning interatomic potentials (MLIPs) offer a powerful avenue for
simulations beyond length and timescales of ab initio methods. Their
development for investigation of mechanical properties and fracture, however,
is far from trivial since extended defects -- governing plasticity and crack
nucleation in most materials -- are too large to be included in the training
set. Using TiB as a model ceramic material, we propose a strategy for
fitting MLIPs suitable to simulate mechanical response of monocrystals until
fracture. Our MLIP accurately reproduces ab initio stresses and failure
mechanisms during room-temperature uniaxial tensile deformation of TiB at
the atomic scale ( atoms). More realistic tensile tests (low
strain rate, Poisson's contraction) at the nanoscale (--10
atoms) require MLIP up-fitting, i.e. learning from additional ab initio
configurations. Consequently, we elucidate trends in theoretical strength,
toughness, and crack initiation patterns under different loading directions. To
identify useful environments for further up-fitting, i.e., making the MLIP
applicable to a wider spectrum of simulations, we asses transferability to
other deformation conditions and phases not explicitly trained on
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