Agriculturización, inequidad distributiva y fractura del tejido social

Los cambios operados en la actividad agrícola en nuestro país a lo largo de las últimas dos décadas, identificados genéricamente bajo la denominación de agriculturización, han generado múltiples impactos, muchos de ellos de carácter contradictorio. Así, el crecimiento de la actividad económica, el incremento en los saldos exportables y en los recursos fiscales conviven, entre otras manifestaciones, con la agudización de las tensiones derivadas de la concentración económica, con nuevos impactos e incertidumbres de carácter ambiental, con desequilibrios territoriales crecientes, con la ampliación de la brecha laboral y con el incremento en la inequidad distributiva. Este trabajo presenta los resultados de un análisis exploratorio orientado a pequeñas localidades de la región pampeana, en el cual se visualiza el surgimiento de fuertes signos de fractura del tejido social, derivados del crecimiento de la inequidad distributiva de la riqueza en el interior del espacio rural. Dos tendencias fundamentales constituyen los emergentes de este proceso: 1°) los cambios en los estilos de vida de los sectores relacionados con la actividad agrícola, visibles fundamentalmente en modificaciones en las pautas de consumo (sobre todo entre los jóvenes); y 2°) la heterogeneización de las percepciones de los pobladores sobre la valorización del trabajo en la comunidad. La reconstrucción de estos procesos, escasamente abordados en la literatura académica, se realizó a través de estrategias metodológicas que combinan métodos cuanti y cualitativos, tomando como caso de estudio una pequeña localidad en la Provincia de Santa Fe

The Darién Region, Connecting Road of the Americas, among the expressions of hydric wealth, land vocation and the extractive exploration on its violated forms

Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition

The Darién Region, Connecting Road of the Americas, among the expressions of hydric wealth, land vocation and the extractive exploration on its violated forms

Colombia has oceanic waters, catchment areas, like lakes, cienagas and swamps, water flows, like rivers, gorges and streams, small rivers and groundwater. The oceanic waters are the Caribbean Sea-1600 km and the Pacific Ocean-1300 km that comprise the north and west continental territory, respectively. Actually the Region of Darién, geographically bounded by the Carribean Sea to the north is becoming to be focused by studies due to use conflicts and disputes about water and a forest reserve on its territories. Considering its location, strategic at northwestern Colombia, frontier region with Central America, several dynamics are imposed. One of them is the implantation of a road system entitled Connecting Road of the Americas. This fact means the construction of an infra-structure that will cross a special zone formed by swamps and jungle known as The Darién Gap. Evidences of such interests are revealed by projects like the constructions of Turbo's Port in the Atlantic Ocean, Department of Antioquia and Tribugá's Port in the Pacific Ocean, Department of Choco, the mountain road and the coastal conection Colombia-Venezuela attending to the main intentions of the central region of the department (Metropolitan Area of Aburrá Valley-AMVA). Human settlements form a productive system, based on small and medium familiar agriculture's production, corresponding to the western portion and piedmont of Abibe's mountain at its antioquian portion, alluvial plan that forms the rivers on this area, the littoral zone that delimits the Carribean Sea, the Darién and Baudó Mountains and the gulf that receives, among other waters, the ones from Atrato and León, as well as the exodus process constitutes a forced exit resulting from actions of several armed groups. It can be identified intense historical, cultural, political and environmental relations, specially the last one associated with strategic ecosystems that are fundamental for the hydric regulation of the region, as well as food safety of the local inhabitants. Results from two researches (UPB, 2007 y 2010) reveals this quick transformation in the spatial re-configuration, demographical and economical indicators and the exacerbated fight for resources, damaging the extractive vocation in the Region. Path to commerce of illegalities (drugs, guns) and to implementation of the agroindustrial project for biofuel production, cooperation program that involves Venezuela, Brazil and Colombia. Appropriation modes allow the existence of strategies since global interests revealing a development logic that privileges the conception of an artificialized nature. Since the smallest portion of rural areas, specific modes of resources exploration are linked to imposed interests of transnational corporations. Disparate consequences are going deeper evidenced by social, technical and nature transformations, envisioning risks for the habitability's condition

El estado como eje articulador de las relaciones sociales

El presente trabajo intenta realizar una síntesis de cómo se fue articulando la sociedad a partir del modelo capitalista de producción en el período histórico que transcurre desde el impulso desarrollado en la Segunda Revolución Industrial, a finales del siglo XIX , hasta la primera década del siglo XXI. Este período determinará una forma de integración social que va estar vinculada al trabajo asalariado y ligada a un Estado más presente, articulador y distribuidor de la riqueza social. Algunos de los elementos constitutivos que sostuvieron este modelo fueron el New Deal y la política económica keynesiana, que van a perdurar hasta bien entrada la década de 1970. En esta etapa, la relación capital-trabajo va a entrar en crisis; el modelo keynesiano de pleno empleo no le es útil al capitalismo; y, por lo tanto, el Estado va a permitir la incorporación de un nuevo discurso, enarbolado por los denominados economistas liberales ortodoxos y, ya en la última década del siglo XX , por el economista norteamericano John Williamson, relacionado con un movimiento intelectual denominado "Consenso de Washington"; esto dando lugar una nueva forma de estructuración social en la que van a coexistir ganadores y perdedores del sistema. Se intenta explicar, además, el impacto que provocó en la Argentina adherir al modelo neoliberal a través de una economía abierta (1989-2002). Por último, describimos la situación de la Provincia de San Luis; los dispositivos y mecanismos que utilizó para contrarrestar los dos dígitos de desocupación producidos después del año 2002; para ello, nos referimos al Plan de Inclusión Social, expuesto a través de datos estadísticos tomados del INDEC y de la Dirección Provincial de Estadísticas y Censos de la Provincia de San Luis

Agriculturización, inequidad distributiva y fractura del tejido social

Los cambios operados en la actividad agrícola en nuestro país a lo largo de las últimas dos décadas, identificados genéricamente bajo la denominación de agriculturización, han generado múltiples impactos, muchos de ellos de carácter contradictorio. Así, el crecimiento de la actividad económica, el incremento en los saldos exportables y en los recursos fiscales conviven, entre otras manifestaciones, con la agudización de las tensiones derivadas de la concentración económica, con nuevos impactos e incertidumbres de carácter ambiental, con desequilibrios territoriales crecientes, con la ampliación de la brecha laboral y con el incremento en la inequidad distributiva. Este trabajo presenta los resultados de un análisis exploratorio orientado a pequeñas localidades de la región pampeana, en el cual se visualiza el surgimiento de fuertes signos de fractura del tejido social, derivados del crecimiento de la inequidad distributiva de la riqueza en el interior del espacio rural. Dos tendencias fundamentales constituyen los emergentes de este proceso: 1°) los cambios en los estilos de vida de los sectores relacionados con la actividad agrícola, visibles fundamentalmente en modificaciones en las pautas de consumo (sobre todo entre los jóvenes); y 2°) la heterogeneización de las percepciones de los pobladores sobre la valorización del trabajo en la comunidad. La reconstrucción de estos procesos, escasamente abordados en la literatura académica, se realizó a través de estrategias metodológicas que combinan métodos cuanti y cualitativos, tomando como caso de estudio una pequeña localidad en la Provincia de Santa Fe

CO2-driven ocean acidification alters and weakens integrity of the calcareous tubes produced by the serpulid tubeworm, Hydroides elegans

As a consequence of anthropogenic CO2-driven ocean acidification (OA), coastal waters are becoming increasingly challenging for calcifiers due to reductions in saturation states of calcium carbonate (CaCO3) minerals. The response of calcification rate is one of the most frequently investigated symptoms of OA. However, OA may also result in poor quality calcareous products through impaired calcification processes despite there being no observed change in calcification rate. The mineralogy and ultrastructure of the calcareous products under OA conditions may be altered, resulting in changes to the mechanical properties of calcified structures. Here, the warm water biofouling tubeworm, Hydroides elegans, was reared from larva to early juvenile stage at the aragonite saturation state (Omega A) for the current pCO2 level (ambient) and those predicted for the years 2050, 2100 and 2300. Composition, ultrastructure and mechanical strength of the calcareous tubes produced by those early juvenile tubeworms were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and nanoindentation. Juvenile tubes were composed primarily of the highly soluble CaCO3 mineral form, aragonite. Tubes produced in seawater with aragonite saturation states near or below one had significantly higher proportions of the crystalline precursor, amorphous calcium carbonate (ACC) and the calcite/aragonite ratio dramatically increased. These alterations in tube mineralogy resulted in a holistic deterioration of the tube hardness and elasticity. Thus, in conditions where Omega A is near or below one, the aragonite-producing juvenile tubeworms may no longer be able to maintain the integrity of their calcification products, and may result in reduced survivorship due to the weakened tube protection.

The effects of growth phase and salinity on the hydrogen isotopic composition of alkenones produced by coastal haptophyte algae

The isotopic fractionation of hydrogen during the biosynthesis of alkenones produced by marine haptophyte algae has been shown to depend on salinity and, as such, the hydrogen isotopic composition of alkenones is emerging as a palaeosalinity proxy. The relationship between fractionation and salinity has previously only been determined during exponential growth, whilst it is not yet known in which growth phases natural haptophyte populations predominantly exist. We have therefore determined the relationship between the fractionation factor, alpha alkenones-water, and salinity for C37 alkenones produced in different growth phases of batch cultures of the major alkenone-producing coastal haptophytes Isochrysis galbana (strain CCMP 1323) and Chrysotila lamellosa (strain CCMP 1307) over a range in salinity from ca. 10 to ca. 35. alpha alkenones-water was similar in both species, ranging over 0.841-0.900 for I. galbana and 0.838-0.865 for C. lamellosa. A strong (0.85 <= R**2 <= 0.97; p < 0.0001) relationship between salinity and fractionation factor was observed in both species at all growth phases investigated. This suggests that alkenone dD has the potential to be used as a salinity proxy in coastal areas where haptophyte communities are dominated by these coastal species. However, there was a marked difference in the sensitivity of alpha alkenones-water to salinity between different growth phases: in the exponential growth phase of I. galbana, alpha alkenones-water increased by 0.0019 per salinity unit (S 1), but was less sensitive at 0.0010 S 1 and 0.0008 S 1 during the stationary and decline phases, respectively. Similarly, in C. lamellosa alpha alkenones-water increased by 0.0010 S 1 in the early stationary phase and by 0.0008 S 1 during the late stationary phase. Assuming the shift in sensitivity of alpha alkenones-water to salinity observed at the end of exponential growth in I. galbana is similar in other alkenone-producing species, the predominant growth phase of natural populations of haptophytes will affect the sensitivity of the alkenone salinity proxy. The proxy is likely to be most sensitive to salinity when alkenones are produced in a state similar to exponential growth.

Analysis and optimization of propagation losses in LiNbO3 optical waveguides produced by swift heavy-ion irradiation

The propagation losses (PL) of lithium niobate optical planar waveguides fabricated by swift heavy-ion irradiation (SHI), an alternative to conventional ion implantation, have been investigated and optimized. For waveguide fabrication, congruently melting LiNbO3 substrates were irradiated with F ions at 20 MeV or 30 MeV and fluences in the range 1013–1014 cm−2. The influence of the temperature and time of post-irradiation annealing treatments has been systematically studied. Optimum propagation losses lower than 0.5 dB/cm have been obtained for both TE and TM modes, after a two-stage annealing treatment at 350 and 375∘C. Possible loss mechanisms are discussed.

On the calculation of energy produced by a PV grid-connected system

This study develops a proposal of method of calculation useful to estimate the energy produced by a PV grid-connected system making use of irradiance-domain integrals and denition of statistical moment. Validation against database of real PV plants performance data shows that acceptable energy estimation can be obtained with rst to fourth statistical moments and some basic system parameters. This way, only simple calculations at the reach of pocket calculators, are enough to estimate AC energy.

Genetic fuzzy-based steering wheel controller using a mass-produced car

Intelligent Transportation Systems (ITS) cover a broad range of methods and technologies that provide answers to many problems of transportation. Unmanned control of the steering wheel is one of the most important challenges facing researchers in this area. This paper presents a method to adjust automatically a fuzzy controller to manage the steering wheel of a mass-produced vehicle to reproduce the steering of a human driver. To this end, information is recorded about the car's state while being driven by human drivers and used to obtain, via genetic algorithms, appropriate fuzzy controllers that can drive the car in the way that humans do. These controllers have satisfy two main objectives: to reproduce the human behavior, and to provide smooth actions to ensure comfortable driving. Finally, the results of automated driving on a test circuit are presented, showing both good route tracking (similar to the performance obtained by persons in the same task) and smooth driving.

Low-speed longitudinal controllers for mass-produced cars: A comparative study

Four longitudinal control techniques are compared: a classical Proportional-Integral (PI) control; an advanced technique-called the i-PI-that adds an intelligent component to the PI; a fuzzy controller based on human experience; and an adaptive-network-based fuzzy inference system. The controllers were designed to tackle one of the challenging topics as yet unsolved by the automotive sector: managing autonomously a gasoline-propelled vehicle at very low speeds. The dynamics involved are highly nonlinear and constitute an excellent test-bed for newly designed controllers. A Citroën C3 Pluriel car was modified to permit autonomous action on the accelerator and the brake pedals-i.e., longitudinal control. The controllers were tested in two stages. First, the vehicle was modeled to check the controllers' feasibility. Second, the controllers were then implemented in the Citroën, and their behavior under the same conditions on an identical real circuit was compared.