The Effect of \u3cem\u3eLeucaena leucocephala\u3c/em\u3e on Beef Production and Toxicity in the Chaco Region of Argentina

Hedgerows of the fodder tree legume, Leucaena leucocephala (Lam.) de Wit ssp. glabrata (Rose Zárate) (leucaena), planted with companion grass, provide productive, profitable and sustainable tropical pasture (Shelton and Dalzell 2007). Although leucaena can improve beef production from tropical pastures, poor grower adoption has limited development of leucaena in the Chaco Region of Argentina. This can be partly attributed to: (1) unsuccessful establishment; (2) limited understanding of leucaena management as a forage resource; and (3) concerns about mimosine toxicity. These 3 limitations have been overcome in other regions of the world (e.g. northern Australia and the Chaco Region of Paraguay), but little is known about leucaena management and the protection status of ruminants against mimosine toxicosis in Argentina. The objective of this study was to evaluate the effect of leucaena on beef production and toxicity in the west of the Argentinean Chaco Region. We hypothesise that the introduction of leucaena into grass pastures will significantly increase beef productivity if mimosine toxicosis does not appear

Le Peneroplidi dei sedimenti recenti del Mediterraneo e del Golfo Persico

Questa nota riguarda lo studio di popolazioni differenti di Peneroplidi e le loro variazioni morfologiche individuali. I campioni sono stati prelevati, sempre a debole profondità, vicino alla costa. In Sardegna lungo la spiaggia di Golfo Aranci, nel Golfo Persico lungo la spiaggia di Aziziyah (a 1O Km circa a Sud di Alkhobar) e nella laguna interna Rawhat as Sayh

The effect of Leucaena leucocephala on beef production and its toxicity in the Chaco Region of Argentina

Hedgerows of the fodder tree legume, Leucaena leucocephala ssp. glabrata (leucaena), planted with a companion grass, provide productive, profitable and sustainable tropical pasture (Shelton and Dalzell 2007). Although leucaena can improve beef production, poor grower adoption has limited development of leucaena in the Chaco Region of Argentina. Factors contributing to poor adoption include: (1) unsuccessful establishment; (2) limited understanding of leucaena management as a forage resource; and (3) concerns about mimosine toxici-ty. While these 3 limitations have been overcome in other regions of the world (e.g. northern Australia and the Chaco Region of Paraguay), in Argentina little is known about leucaena management and the protection of ruminants against mimosine toxicosis.Instituto de Investigación Animal del Chaco SemiáridoFil: Radrizzani Bonadeo, Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; Argentina.Fil: Nasca, Jose Andres. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; Argentina

Soil Organic Carbon and Total Nitrogen in a \u3ci\u3eLeucaena leucocephala\u3c/i\u3e Silvopastoral System in the Chaco Region, Argentina

The introduction of leucaena (Leucaena leucocephala) into hedgerow silvopastoral systems increases animal production and improves soil fertility, through biological nitrogen fixation and deep-rooted leguminous trees. There is limited information on carbon and nitrogen dynamics in hedgerow silvopastoral systems, particularly in long term periods and subsoil profiles. The concentrations and vertical distribution of organic carbon (OC) and total nitrogen (TN), and their fractions (particulate and associate forms) in the soil profile (0‒100 cm), with and without leucaena were compared 10 years after leucaena establishment into a 24-year-old tropical pasture (Urochloa brizantha-Chloris gayana). Leucaena increased the OC concentration in the deepest horizon (50‒100 cm) by 73% (from 0.40 to 0.69%), particularly the stable form (associate OC). This was attributed to a greater abundance of leucaena roots deeper in the profile than in the pure grass pasture. Leucaena also enhanced by 12% the TN concentration in the topsoil (0‒20 cm) (from 0.133 to 0.149%) and by 21% in deepest horizon (from 0.049 to 0.059%) associated with leaf deposition, recycling of animal feces and nodule-N turnover from N fixation. Although TN increased in the leucaena topsoil and it is expected that OC follows the same pattern, OC concentration decreased in the topsoil. The low OC content in the topsoil of the leucaena pasture was closely linked to the poor grass cover observed (r2 = 0.82). The loss in grass cover was attributed to the excessive grazing pressure imposed to control the height of leucaena hedgerows. Leucaena establishment has the potential to improve soil fertility and hence availability of N to companion grass growth, and can be utilized as a greenhouse gas mitigation strategy. However, to achieve the potential productivity and carbon sequestration of leucaena in silvopastoral systems, grass persistence needs to be evaluated under different management practices and grazing regimes

The “Fragment”: Fichte’s First Answer to Jacobi’s “Letter”

This article examines the aspects of the so-called “quarrel over atheism” between F. H. Jacobi and Fichte. In 1799 Jacobi writes the famous Letter to Fichte, in which the doctrine of science is designated as nihilistic. Special attention is paid to Fichte's unpublished response Rükerinnerungen, Antworten, Fragen (Recollections, answers, questions) and to the fragment of a letter to Jacobi and Reinhold. In this fragment, Fichte emphasizes the opposition between his philosophy and Jacobi’s philosophy, which corresponds to the opposition between the point of view of life and that of speculation. Although they are opposites, they can coexist with equal right as long as one does not try to legislate over the other.  Este artigo examina alguns aspectos da “querela sobre o ateísmo” entre F. H. Jacobi e Fichte. Em 1799, Jacobi redige a Carta a Fichte, na qual a doutrina da ciência é designada como niilista. Especial atenção será dada à resposta pouco conhecida e não publicada de Fichte Rükerinnerungen, Antworten, Fragen (Reminiscências, respostas, perguntas) e ao fragmento de uma carta que Fichte envia a Jacobi e Reinhold. Ali, Fichte ressalta a oposição entre sua filosofia e a de Jacobi, que equivale à oposição entre o ponto de vista da vida e da especulação. Embora ambos sejam contrários, podem coexistir com igual direito, desde que um não queira legislar sobre o outro.  

Reinhold et l’héritage de Bode

Cet article se fixe pour but d’examiner l’articulation entre l’engagement Maçonnique de Reinhold et sa carrière philosophique dans les années 1788–1794. Cette période est marquée par un événement majeur, qui survient en décembre 1793: la mort de Johann Christoph Bode, qui, après la crise de l’Illuminisme survenue en 1787, s’était appliqué à redéfinir l’orientation de l’Ordre. Reinhold, qui avait été étroitement associé aux travaux de Bode, se sent appelé à endosser son héritage

Les raisons systématiques de l’inachèvement du système fichtéen

For some years Fichte seems to have envisioned the possibility of presenting a definitive and final version of his Science of Knowledge. This article develops two reasons why such a project is structurally impossible. On the one hand, Fichte, inspired by the tradition of negative theology, challenges the capacity of language of being pure performativity: it always involves an element of letter which prevents it from being all spirit. On the other hand, the opening of the system to life implies a kind of incompleteness which is the only possible and consistent with the idea of the Doctrine of Science (understood as closed system of transcendental conditions of consciousness). More precisely, the specific completion of the Doctrine of Science cannot tolerate another kind of incompletion but that resulting of the opening to the life required by the system

Les raisons systématiques de l’inachèvement du système fichtéen

For some years Fichte seems to have envisioned the possibility of presenting a definitive and final version of his Science of Knowledge. This article develops two reasons why such a project is structurally impossible. On the one hand, Fichte, inspired by the tradition of negative theology, challenges the capacity of language of being pure performativity: it always involves an element of letter which prevents it from being all spirit. On the other hand, the opening of the system to life implies a kind of incompleteness which is the only possible and consistent with the idea of the Doctrine of Science (understood as closed system of transcendental conditions of consciousness). More precisely, the specific completion of the Doctrine of Science cannot tolerate another kind of incompletion but that resulting of the opening to the life required by the system

Non-Invasive Experimental Identification of a Single Particle Model for LiFePO4 Cells

The rapid spread of Lithium-ions batteries (LiBs) for electric vehicles calls for the development of accurate physical models for Battery Management Systems (BMSs). In this work, the electrochemical Single Particle Model (SPM) for a high-power LiFePO4 cell is experimentally identified through a set of non-invasive tests (based on voltage-current measurements only). The SPM is identified through a two-step procedure in which the equilibrium potentials and the kinetics parameters are characterized sequentially. The proposed identification procedure is specifically tuned for LiFePO4 chemistry, which is particularly challenging to model due to the non-linearity of its open circuit voltage (OCV) characteristic. The identified SPM is compared with a second-order Equivalent Circuit Model (ECM) with State of Charge dependency. Models performance is compared on dynamic current profiles. They exhibit similar performance when discharge currents peak up to 1C (RMSE between simulation and measures smaller than 20 mV) while, increasing the discharge peaks up to 3C, ECM's performance significantly deteriorates while SPM maintains acceptable RMSE (< 50 mV).Comment: Accepted for publication at the IFAC World Congress 202

An Add-on Model Predictive Control Strategy for the Energy Management of Hybrid Electric Tractors

The hybridization process has recently touched also the world of agricultural vehicles. Within this context, we develop an Energy Management Strategy (EMS) aiming at optimizing fuel consumption, while maintaining the battery state of charge. A typical feature of agricultural machines is that their internal combustion engine is speed controlled, tracking the reference requested by the driver. In view of avoiding any modification on this original control loop, an add-on EMS strategy is proposed. In particular, we employ a multi-objective Model Predictive Control (MPC), taking into account the fuel consumption minimization and the speed tracking requirement, including the engine speed controller in the predictive model. The proposed MPC is tested in an experimentally-validated simulation environment, representative of an orchard vineyard tractor.Comment: Submitted to IEEE Transactions on Vehicular Technolog