764 research outputs found
Assessing the Sustainable Development Dimensions of Environmental Public Policies for Protected Natural Areas in Mexico: A 1970-2018 Perspective
Abstract: This abstract discusses the challenges and issues related to the implementation of Environmental Public Policies (EPP) for Protected Natural Areas (PNA) in Mexico from 1970 to 2018. EPPs aim to achieve sustainable development by balancing economic, environmental, and social dimensions while reconciling conservation and the use of natural resources with restrictions on their use and economic compensation to communities. However, the results of this study reveal that the establishment of PNA has been unilateral and without consensus, leading to limitations on communities\u27 use of the environment without granting them economic compensation or productive alternatives. This has resulted in conflicts from the use of natural resources (CUNR). To address these issues, the paper recommends increasing the budget of programs that support productive activities for populations and building partnerships among the populations and public policies. This research highlights the importance of considering the socio-economic impacts of environmental policies to ensure their success and sustainability in the long term
On the physics of transient ejection from bubble bursting
Using a dynamical scaling analysis of the flow variables and their evolution due to bubble bursting, here we predict the size and speed of ejected droplets for the whole range of experimental Ohnesorge and Bond numbers where ejection occurs. The transient ejection, which requires the backfire of a vortex ring inside the liquid to preserve physical symmetry, shows a delicate balance between inertia, surface tension and viscous forces around a critical Ohnesorge number, akin to an apparent singularity. Like in other natural phenomena, this balance makes the process extremely sensitive to initial conditions. Our model generalizes or displaces other recently proposed ones, impacting on, for instance, the statistical description of sea spray.Ministerio de Economía, Industria y Competitividad DPI2016-78887Ministerio de Economía, Industria y Competitividad PID2019-108278RBJunta de Andalucía P18-FR-362
The onset of electrospray: the universal scaling laws of the first ejection
The disintegration of liquid drops with low electrical conductivity and subject to an electric field
is investigated both theoretically and experimentally. This disintegration takes place through the
development of a conical cusp that eventually ejects an ultrathin liquid ligament. A first tiny drop is
emitted from the end of this ligament. Due to its exceptionally small size and large electric charge per
unit volume, that drop has been the object of relevant recent studies. In this paper, universal scaling
laws for the diameter and electric charge of the first issued droplet are proposed and validated both
numerically and experimentally. Our analysis shows how charge relaxation is the mechanism that
differentiates the onset of electrospray, including the first droplet ejection, from the classical steady
cone-jet mode. In this way, our study identifies when and where charge relaxation and electrokinetic
phenomena come into play in electrospray, a subject of live controversy in the field.Ministerio de Economía y Competitividad DPI2013-4648
Interplay between the vortex phase coherence and extended disorder defects in the vortex-liquid regime of thin films and superlattices of 123 superconductors
a-axis oriented (CuO_2 planes perpendicular to the substrate) films and superlattices grown on cubic substrates show a structure with 90° microdomains. The microdomains are grains with a 90° rotation of the c axis. In the vortex liquid region, this microstructure induces a change from the usual three-dimensional (3D) behavior of the anisotropy toward a 2D behavior, in a temperature range above the usual crossover from 2D to 3D. Moreover, when the thickness of the superconducting part of the multilayers becomes smaller (or of the same order as) than the microdomain size the 3D dimensional anisotropy behavior is recovered
Vortex breakdown in a water-spout flow
The numerical study of the steady axisymmetric air-water flow in a vertical sealed cylinder, driven by the rotating top disk, describes topological transformations as the rotation intensifies. The air meridional flow (AMF) and swirl induce meridional motions of opposite directions in water. For slow (fast) rotation, the effect of AMF (swirl) dominates. For very fast rotation, large-scale regions of clockwise meridional circulation in air and water are separated by a thin layer of anticlockwise circulation adjacent to the interface in water. This pattern develops for other fluids as well. Physical reasoning behind the flow evolution is provided
Ferromagnetic proximity effect in a-Co_xSi_(1-x)/Nb bilayers: Role of magnetic disorder and interface transparency
The superconducting and magnetic properties of a-Co_(x)Si_(1−x) /Nb bilayers have been studied as a function of Co content in order to analyze the superconducting/ferromagnetic proximity effect in a system with strong disorder in the magnetic layers. As Co atoms become more diluted, the magnetization of the amorphous a-CoxSi1−x alloy decreases gradually, whereas their resistivity increases and enters in a weak localization regime. The superconducting transition temperatures of the a-Co_(x)Si_(1−x) /Nb bilayers follow a decreasing trend as Co content is reduced, reaching the lowest value at the boundary between the ferromagnetic-nonmagnetic amorphous phases. These results can be understood in terms of the increase in interface transparency together with the changes in the spin-flip scatterin
Consideraciones sobre la integración de las actividades de salud mental en la atención primaria.
En la compleja situación político-sanitaria en que nos movemos parecen ir delimitándose poco a poco algunos elementos de lo que probablemente van a ser las líneas generales que va a enmarcarse la evolución a medio plazo de nuestras estructuras sanitarias. En este sentido, el recientemente difundido Anteproyecto de Ley General de Sanidad (Ministerio de Sanidad y Consumo, 1984) establece con aceptable nitidez los elementos estructurales que presumiblemente van a presidir la organización del futuro Servicio Nacional de Salud en el marco del llamado «Estado de las Autonomías», fijando así los límites a que habrán de adaptarse las actividades sanitarias públicas
Consideraciones sobre la integración de las actividades de salud mental en la atención primaria.
En la compleja situación político-sanitaria en que nos movemos parecen ir delimitándose poco a poco algunos elementos de lo que probablemente van a ser las líneas generales que va a enmarcarse la evolución a medio plazo de nuestras estructuras sanitarias. En este sentido, el recientemente difundido Anteproyecto de Ley General de Sanidad (Ministerio de Sanidad y Consumo, 1984) establece con aceptable nitidez los elementos estructurales que presumiblemente van a presidir la organización del futuro Servicio Nacional de Salud en el marco del llamado «Estado de las Autonomías», fijando así los límites a que habrán de adaptarse las actividades sanitarias públicas
Consideraciones sobre la integración de las actividades de salud mental en la atención primaria.
En la compleja situación político-sanitaria en que nos movemos parecen ir delimitándose poco a poco algunos elementos de lo que probablemente van a ser las líneas generales que va a enmarcarse la evolución a medio plazo de nuestras estructuras sanitarias. En este sentido, el recientemente difundido Anteproyecto de Ley General de Sanidad (Ministerio de Sanidad y Consumo, 1984) establece con aceptable nitidez los elementos estructurales que presumiblemente van a presidir la organización del futuro Servicio Nacional de Salud en el marco del llamado «Estado de las Autonomías», fijando así los límites a que habrán de adaptarse las actividades sanitarias públicas
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