181 research outputs found
Effective interactions for the SM fermion mass hierarchy and their possible UV realization
We built an extended 2HDM theory with a spontaneously broken
global symmetry, where the tree level Universal Seesaw Mechanism generates the
mass hierarchy of the Standard Model charged fermions and the Zee-Babu
mechanism produces tiny active neutrino masses. The third family of SM charged
fermions gets tree level masses from Yukawa interactions involving the Higgs
doublets (for the top quark) and (for the bottom quark and tau
lepton). The model under consideration is consistent with SM fermion masses and
mixings, with the muon and electron anomalies and successfully
accommodates the constraints arising from charged lepton flavor violation and
meson oscillations. The proposed model predicts rates for charged lepton flavor
violating decays within the reach of forthcoming experiments.Comment: 16 pages, 6 captioned figure
Decomposition and nitrogen mineralisation of two wild lupins (Leguminosae) species with potential as green manures
The amount of biomass produced by various native species of genus Lupinus (L.) growing in Mexico ranges from 2.9- 8.2 Mg/ha of dry matter, which can add up to 200 kg/ha of N to soil as green manure. However, information is scarce on the decomposition and mineralisation this biomass in the soil. The above-ground decomposition and N mineralisation of Lupinus mexicanus Cerv. ex Lag. and Lupinus rotundiflorus M.E. Jones species from Mexico using fine-mesh litter bags was evaluated. Litter bags containing 5 g of above-ground air-dried biomass at the vegetative and flowering stages were buried at a depth of 20 cm. Were dug up every 3 weeks over the course of 4 months, dried and re-weighed to determine the lost mass and total N by the Kjeldahl method. The largest decrease in residue mass occurred during the first 3 weeks of incubation. However, the lost mass was higher in younger green manure (75 days old) than in older plants (85 days old) after 18 weeks of exposure in the field. It was found that 60-75% of the total N in the plant material was released in the first 6 weeks. In L. rotundiflorus green manure, it was found that 79.14% of the initial N in the vegetative stage and 77.6% of N in the flowering stage was released 18 weeks after litter bag installation, whereas L. mexicanus were 74.6% and 74.7%, respectively. It was found that both decomposition and N mineralisation occurred quickly in the green manures evaluated
Industrialización de la riqueza vegetal: oportunidades sociales y económicas
Las empresas enfrentan un importante desafío es esta economía globalizada, porque para sobrevivir tienen que ofrecer nuevos productos con valor agregado en los mercados internacionales. Para ello se requieren profesionales entrenados en las metodologías para el desarrollo de nuevos productos (DNP), y los egresados universitarios tienen que tener estas habilidades para que puedan contribuir a enfrentar esta situación. J unto con esto se requieren también productos innovadores de la mano con la conservación del medio ambiente y aprovechando al máximo los recursos disponibles, bien sea de la tierra o de transformación tecnológica. Con este proyecto se pretende abrir una ventana de oportunidad para que los alumnos del programa de Ingeniería de Procesos puedan adquirir el entrenamiento necesario para desempeñarse con éxito en el DNP. A demás, los empresarios del campo puedan obtener un valor agregado para sus productos como alternativa en tiempos de precios desfavorables.Companies face a major challenge is this globalized economy, because to survive they have to offer new products with added value in the international market. This requires professionals trained in the methodologies for the development of new products (DNP) and university graduates must have these skills so that they can contribute to deal with this situation. A long with this they also require innovations running by the side of conservation of the environment and the taking of full advantage of available resources, either from land or technological transformation. This project is to open a window of opportunity so that the Process Engineering students can acquire the knowledge needed to perform successfully in the DNP training. A lso field employers can get valueadded products as an alternative in times of unfavourable prices
Disorder Induced Diffusive Transport In Ratchets
The effects of quenched disorder on the overdamped motion of a driven
particle on a periodic, asymmetric potential is studied. While for the
unperturbed potential the transport is due to a regular drift, the quenched
disorder induces a significant additional chaotic ``diffusive'' motion. The
spatio-temporal evolution of the statistical ensemble is well described by a
Gaussian distribution, implying a chaotic transport in the presence of quenched
disorder.Comment: 10 pages, 4 EPS figures; submitted to Phys. Rev. Letter
Participación comunitaria y procesos de comunicación en la implementación de programas de reasentamiento de familias dentro del contexto del desarrollo urbano en Barranquilla (Colombia)
Planning processes of development and growth of the city of Barranquilla have required the relocation of the population living in areas of intervention actions. As part of the implementation of the New Management Plan Territorial (POT), the city plans to revitalize an area around the Magdalena River with a view to improving the quality of life of citizens and to increase competitiveness of the city. The revitalization project is known as project “La Loma “. Under the current Land Use Plan of Barranquilla (POT), the urban development project “La Loma” includes, among other activities, the transfer of a large number of people currently living in this area. For this reason, this article aims to review the current POT and documents from City Council and the Mayor’s office associated with the POT and “La Loma” project, in order to identify and analyze the component of community participation and communication related to the implementation of this project. The results of the documents revealed the presence of regulatory elements associated with community participation. The results also showed potentially useful spaces for the implementation of inclusive communication processes. Therefore, this article proposes a guide for the formulation of a strategic communication plan with a focus on participatory communication and dialogue facilitator to be used during the execution of urban projects that include the relocation of families. © 2016, Universidad del Norte. All rights reserved
From local monitoring to a broad‐scale viability assessment: a case study for the Bonelli's Eagle in western Europe
Population viability analysis (PVA) has become a basic tool of current conservation practice. However, if not accounted for properly, the uncertainties inherent to PVA predictions can decrease the reliability of this type of analysis. In the present study, we performed a PVA of the whole western European population (France, Portugal, and Spain) of the endangered Bonelli's Eagle (Aquila fasciata), in which we thoroughly explored the consequences of uncertainty in population processes and parameters on PVA predictions. First, we estimated key vital rates (survival, fertility, recruitment, and dispersal rates) using monitoring, ringing, and bibliographic data from the period 1990-2009 from 12 populations found throughout the studied geographic range. Second, we evaluated the uncertainty about model structure (i.e., the assumed processes that govern individual fates and population dynamics) by comparing the observed growth rates of the studied populations with model predictions for the same period. Third, using the model structures suggested in the previous step, we assessed the viability of both the local populations and the overall population. Finally, we analyzed the effects of model and parameter uncertainty on PVA predictions. Our results strongly support the idea that all local populations in western Europe belong to a single, spatially structured population operating as a source-sink system, whereby the populations in the south of the Iberian Peninsula act as sources and, thanks to dispersal, sustain all other local populations, which would otherwise decline. Predictions regarding population dynamics varied considerably, and models assuming more constrained dispersal predicted more pessimistic population trends than models assuming greater dispersal. Model predictions accounting for parameter uncertainty revealed a marked increase in the risk of population declines over the next 50 years. Sensitivity analyses indicated that adult and pre‐adult survival are the chief vital rates regulating these populations, and thus, the conservation efforts aimed at improving these survival rates should be strengthened in order to guarantee the long‐term viability of the European populations of this endangered species. Overall, the study provides a framework for the implementation of multi‐site PVAs and highlights the importance of dispersal processes in shaping the population dynamics of long‐lived birds distributed across heterogeneous landscapes
A randomized study of nutritional supplementation in patients with unilateral wet age-related macular degeneration
The purpose of this study is evaluate the efficacy and safety of medicinal products con-taining the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, random-ized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of -1.63 (95% CI -0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
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