Spatial and temporal variability of CO2 emisions in soils under conventional tillage and no-till farming

Agricultural soils can act as a carbon sink depending on the soil management practices employed. As a result of this functional duality, soil management systems are present in international documents relating to climate change mitigation. Agricultural practices are responsible for 14% of total greenhouse gas emissions (GHG’s) (MMA, 2009)(1). Conservation agriculture (CA) is one of the most effective agricultural systems for reducing CO2 emissions, as it increases the sequestration of atmospheric carbon in the soil. In order to assess the performance of CA in terms of CO2 emissions, a field trial was conducted comparing soil derived CO2 fluxes under No-till (NT) farming and under conventional tillage. Three pilot farms were selected in the cereal-growing area of southern Spain, located in Las Cabezas de San Juan (Seville), Carmona (Seville) and Cordoba. Each pilot farm comprises six experimental plots with an approximate area of five hectares; three of the six plots implement CA practices, while the other three use conventional tillage techniques. The subdivision of each tillage system into 3 plots allowed the simultaneous cropping of the three crops of the wheat-sunflower-legume rotation each year. Results showed that carbon dioxide emissions were 31 to 91% higher in tilled soils than in untilled soils, and that there was a great seasonal variability of CO2 emissions, as weather conditions also differed considerably for the different sampling periods. In all cases, the CO2 fluxes emitted into the atmosphere were always higher when soil was subject to conventional tillage

Effect of agronomic and environmental factors on CO2 emissions on a dryland rotation

Agriculture is a substantial source of greenhouse gas emissions (GHG) in many countries. Conservation agriculture includes soil management systems that help to reduce CO2 emission levels. However, there are many factors involved in the production of these emissions such as soil management type and time at which the agriculture operations are performed, crop phenological state, the weather, and handling of the residue amongst others. In the long term, the relationships that exist between these factors seem to determine the balance of these emissions. In this study, we analyzed the influence of the soil management system as well as the climatology of the different seasons studied and the phenological state of the different crops implanted. For this purpose a field trial was conducted in Las Cabezas de San Juán (Seville). This pilot farm consisted of six experimental plots with an approximate area of 5 ha; conservation agriculture practices were employed in three of the six plots while traditional tillage management was used in the other three. Within these plots the three crops of the wheat-sunflower-legume rotation were tested simultaneously. The study was conducted over four agricultural seasons - 2009/10, 2010/11, 2011/12 and 2012/13. Each of these cropping seasons were characterised by very different rainfall amounts, registering a total of 814.4, 721.6, 268.2 and 676.4 l/m2, respectively. When we studied the evolution of emissions over four seasons, an increase could be observed for both management systems during the time in which the crops were established due to the roots respiration processes. These increases were heavily influenced by the rainfall recorded during the time in which the crop was in place. In the case of wheat, higher emissions were produced during the cultivation time of the first and fourth season during which 84% and 60% of the total rainfall of each season was recorded. These emissions were 9 and 5 kg CO2/ha for conventional tillage and no tillage, respectively for the 2009/10 season and 11.7 and 6.8 kg CO2/ha, respectively in the 2012/13 season. Conversely during the 2011/12 season, a season in which lower precipitation was registered, the higher emissions were comparatively minor with respect to the previous values, specifically 3.7 and 1.9 kg CO2/ha for non-tillage and conventional tillage

The cg-average tree value for games on cycle-free fuzzy communication structures

The main goal in a cooperative game is to obtain a fair allocation of the profit due the cooperation of the involved agents. The most known of these allocations is the Shapley value. This allocation considers that the communication among the players is complete. The Myerson value is a modification of the Shapley value considering a communication structure which determines the feasible bilateral relationships among the agents. This allocation of the profit is not always a stable solution. Another payoff allocation for games with a communication structure from the definition of the Shapley value is the average tree value. This one is a stable solution for any game using a cycle-free communication structure. Later fuzzy communication structures were introduced. In a fuzzy communication structure, the membership of the agents and the relationships among them are leveled. The Myerson value was extended in several different ways depending on the behavior of the agents. In this paper, the average tree value is extended to games with fuzzy communication structures taking one particular version: the Choquet by graphs (cg). We present an application to the management of an electrical network with an algorithmic implementation.Spanish Ministry of Education and Science MTM2017-83455-PAndalusian Government FQM23

Cost-allocation problems for fuzzy agents in a fixed-tree network

Cost-allocation problems in a fixed network are concerned with distributing the costs for use by a group of clients who cooperate in order to reduce such costs. We work only with tree networks and we assume that a minimum cost spanning tree network has already been constructed and now we are interested in the maintenance costs. The classic problem supposes that each agent stays for the entire time in the same node of the network. This paper introduces cost-allocation problems in a fixed-tree network with a set of agents whose activity over the nodes is fuzzy. Agent’s needs to pay for each period of time may differ. Moreover, the agents do not always remain in the same node for each period. We propose the extension of a very well-known solution for these problems: Bird’s rule.Ministerio de Economía y Competitividad MTM2017-83455-PJunta de Andalucía FQM23

Deterioro de la calidad de las aguas de percolación por la aplicación de lodos de depuradora a un suelo agrícola

[ES] El posible deterioro de la calidad de las aguas subterráneas, causado por la aplicación de lodos de depuradora a un suelo agrícola, es evaluado en términos del incremento de la salinidad del agua de recarga y de su contenido en nutrientes. Para ello, se obtuvieron las curvas de lavado de cada elemento en estudio, a partir de un ensayo de lixiviación en columnas de suelo, el cual permitió estimar un intervalo de variación de la dosis de aplicación a adoptar para que hiciera mínima la posibilidad de contaminación del medio. El estudio de los valores de la Relación de Adsorción de Sodio (RAS) en los lixiviados obtenidos, así como de la variación de la conductividad eléctrica (CE) y concentraciones de distintos solutos, hizo posible evaluar la calidad de las aguas de percolación. Estas no presentan ningún riesgo de alcalinización del suelo, presentando valores de CE a tener en cuenta únicamente en los casos correspondientes a dosis del residuo extremas, y de forma transitoria. El fósforo aportado con los lodos de depuradora aumenta con la dosis de aplicación de los mismos, quedando parte fijado en el suelo. La fracción lixiviada podría condicionar la concentración de las aguas subterráneas, si bien sólo para las dosis extremas. En cuanto a la dinámica del nitrógeno inorgánico, las condiciones anaerobias en las que se realizó el ensayo conducen a una concentración de nitratos despreciable en los lixiviados. El aporte directo es en forma amoniacal, quedando retenido en el suelo y siendo asimismo transportado a lo largo del perfil. Las curvas de transporte de este ión para cada dosis adoptada completan el estudio. La evaluación de los aspectos mencionados, esto es, salinidad y aportes de fósforo y nitrógeno, arroja resultados favorables para la aplicación de lodos de depuradora a suelos agrícolas, para las dosis de aplicación indicadas.A Isabel Ordóñez, Catalina Lara, Carmen del Moral, Araceli García y Bienvenido Dugo, por su valiosa colaboración tanto en la toma de muestras como en el análisis de las mismas.Polo Gómez, MJ.; Ordóñez Fernández, R.; Giráldez Cervera, JV. (1996). Deterioro de la calidad de las aguas de percolación por la aplicación de lodos de depuradora a un suelo agrícola. Ingeniería del Agua. 3(4):77-88. https://doi.org/10.4995/ia.1996.2710SWORD778834Ayuso, M., Hernández, T., García, C. y Costa, F. (1992) Utilización de un lodo aerobio como sustitutivo de fertilizantes fosforados inorgánicos. Suelo y Planta, 2:271-280.Chaussod, R et Catroux, G. (1985) Determination de le valeur fertilisante des boues résiduaires. Aptitude a liberer Tazote. Ministère de l'environment et du cadre de vie. Convention d'étude n° 74050.Clarke, R.T. (1973) Mathematical Models in Hydrology. FAO Irrigation and Drainage Paper n. 19. Rome.E.P.A. (1984) Use and Disposal of Municipal WastewaterSludge. Environmental Regulations and Technology, Washington.Loehr, R.C., Jewell, W.J., Novak, J.D., Clarkson, W.W. Friedman, G.S. (1979). Land Application of Wastes. Van Nostrand Reinhold, New York.Noyes Data Corporation USA (1979) Sludge Disposal by Landspreading Techniques. Pollution Technology Review, 58.Polo, M.J., Ordóñez, R. y Giráldez, J.V. (1994) Evaluación del movimiento de agua en un suelo tras la aplicación de lodos de depuradora. XII Jornadas Técnicas sobre Riegos. Pamplona.R.D. 1310/1990 de 29 de Octubre. B.O.E. 262, 1 de Noviembre de 1990.Sommers, L.E. Sotton, A.L. (1980) Use of waste materials as source of phosphorus. In: The role of phosphorus in agriculture. Khsawneh, F.E., Sample, E.C. and Kamprath, E.J. (Ed.). Am. Soc. Agron., Madison.Van Genuchten, M. Th. and Alves, W.J. (1982) Analytical solutions of the one dimensional convection-dispersion solute transpon equation. U.S. Dep. Agric., Teeh. Bull. 1661, 1-151.Van Genuchten, M. Th. Parker, J.C. (1984) Boundary conditions for displacement experiments through short laboratory soil columns. Soil Sci. Soc. Am. J. 48:703-708

Conocimientos, actitudes y prácticas adoptados por los estudian tes de la universidad del quindío frente a la salud sexual y reproductiva

Salud sexual es la forma como enfrento los diferentes riesgos existentes en toda práctica que asuma; existen métodos de protección que me permiten disfrutar de mis experiencias sin correr riesgos de enfermarme o contagiar a alguien; el método más efectivo es el condón. Salud reproductiva es la opción que tengo de elegir cuando iniciar una familia, con quien, y cuantos integrantes. Los métodos de planificación familiar me permiten decidir y no correr el riesgo de tener un embarazo no deseado. Ambas están justificadas en los derechos sexuales y reproductivos que son el pilar de una expresión adecuada de la sexualidad

Extending the north-east limit of the chart of nuclides

The existence of nuclei with exotic combinations of protons and neutrons provides fundamental information on the forces acting between nucleons. The maximum number of neutrons a given number of protons can bind, neutron drip line1, is only known for the lightest chemical elements, up to oxygen. For heavier elements, the larger its atomic number, the farther from this limit is the most neutron-rich known isotope. The properties of heavy neutron-rich nuclei also have a direct impact on understanding the observed abundances of chemical elements heavier than iron in our Universe. Above half of the abundances of these elements are thought to be produced in rapid-neutron capture reactions, r-process, taking place in violent stellar scenarios2 where heavy neutron-rich nuclei, far beyond the ones known up today, are produced. Here we present a major step forward in the production of heavy neutron-rich nuclei: the discovery of 73 new neutron-rich isotopes of chemical elements between tantalum (Z=72) and actinium (Z=89). This result proves that cold-fragmentation reactions3 at relativistic energies are governed by large fluctuations in isospin and energy dissipation making possible the massive production of heavy neutron-rich nuclei, paving then the way for the full understanding of the origin of the heavier elements in our Universe. It is expected that further studies providing ground and structural properties of the nuclei presented here will reveal further details on the nuclear shell evolution along Z=82 and N=126, but also on the understanding of the stellar nucleosyntheis r-process around the waiting point at A~190 defining the speed of the matter flow towards heavier fissioning nuclei

Soft two-meson-exchange nucleon-nucleon potentials. I. Planar and crossed-box diagrams

Pion-meson-exchange nucleon-nucleon potentials are derived for two nucleons in the intermediate states. The mesons we include are (i) pseudoscalar mesons: $\pi, \eta, \eta'$; (ii) vector mesons: $\rho, \omega, \phi$; (iii) scalar mesons: $a_{0}(980), \varepsilon(760), f_{0}(975)$; and (iv) the $J=0$ contribution from the Pomeron. Strong dynamical pair suppression is assumed, and at the nucleon-nucleon-meson vertices Gaussian form factors are incorporated into the relativistic two-body framework using a dispersion representation for the pion- and meson-exchange amplitudes. The Fourier transformations are performed using factorization techniques for the energy denominators. The potentials are first calculated in the adiabatic approximation to all planar and crossed three-dimensional momentum-space $\pi$-meson diagrams. Next, we calculate the $1/M$ corrections.Comment: 28 pages RevTeX, 8 postscript figures; revised version as to appear in Phys. Rev.

Evaluation of Current Methods to Detect Cellular Leucine-Rich Repeat Kinase 2 (LRRK2) Kinase Activity

Background: Coding variation in the Leucine rich repeat kinase 2 gene linked to Parkinson’s disease (PD) promotes enhanced activity of the encoded LRRK2 kinase, particularly with respect to autophosphorylation at S1292 and/or phosphorylation of the heterologous substrate RAB10. Objective: To determine the inter-laboratory reliability of measurements of cellular LRRK2 kinase activity in the context of wildtype or mutant LRRK2 expression using published protocols. Methods: Benchmark western blot assessments of phospho-LRRK2 and phospho-RAB10 were performed in parallel with in situ immunological approaches in HEK293T, mouse embryonic fibroblasts, and lymphoblastoid cell lines. Rat brain tissue, with or without adenovirus-mediated LRRK2 expression, and human brain tissues from subjects with or without PD, were also evaluated for LRRK2 kinase activity markers. Results: Western blots were able to detect extracted LRRK2 activity in cells and tissue with pS1292-LRRK2 or pT73-RAB10 antibodies. However, while LRRK2 kinase signal could be detected at the cellular level with over-expressed mutant LRRK2 in cell lines, we were unable to demonstrate specific detection of endogenous cellular LRRK2 activity in cell culture models or tissues that we evaluated. Conclusion: Further development of reliable methods that can be deployed in multiple laboratories to measure endogenous LRRK2 activities are likely required, especially at cellular resolution