The chronic toxicity is fundamental for toxicological risk assessment, but its correlation with the chemical structures has been studied only little. This is partly due to the complexity of such an experimental test that embraces a plethora of different biological effects and mechanisms of action, making (Q)SAR studies extremely challenging. In this paper we report a predictive in silico study of more than 400 compounds based on two-dimensional chemical descriptors and multivariate analysis. The root mean squared error of the predictive model is 0.73 (in a logarithmic scale) on a leave-one-out cross-validation and is close to the estimated variability of experimental values (0.64). The analysis of the model revealed that the chronic toxicity effects are driven by the bioavailability of the compound that constitutes a baseline effect plus excess toxicity possible described by a few chemical moieties. The results obtained give confidence that this model can be useful for establishing a level of safety concern in the absence of hard toxicological data.

Today, agriculture industry has a significant impact in global greenhouse gas emissions. A large amount of pollutants come from diesel internal combustion engines, widely used in agricultural machinery. Since mechanization in agriculture is fundamental to achieve a proper food production for a growing human population, changes are needed in common agriculture engineering thinking in order to develop new farming machinery that could outperform conventional ones in terms of environmental impact, as well as performance, productivity and safety. Electrification is a feasible solution. A comprehensive review about agricultural machinery electrification is reported in this paper, with a particular focus on hybrid electric tractors and their implements. The introduction of electric drives in farming tractors is discussed in detail by looking at the main findings in literature and considering state-of-the-art technology. Proposals and prototypes from manufacturers are covered too, as well as economic assessments and future trends.

Anda, quítate el vestido, las flores y las trampas. [L.E. AuTE, Anda] RESUMENSe estudian los diferentes modelos de paisaje que se suceden en la Prehistoria e Historia de una comarca del noroeste de la Península Ibérica. Se analizan tanto la distribución del poblamiento y el uso del suelo a la luz de datos geográficos y arqueológicos, como la articulación de organizaciones territoriales supralocales. En concreto se observa la conformación de un espacio simbólico o sagrado en un sector concreto de la zona de estudio que habría servido como recurso fundamental para configurar y expresar los modelos de paisaje social de cada momento. Con ello se pretenden mostrar las diferentes formas de racionalidad que se esconden detrás de la concepción de lo sagrado a lo largo de varias etapas culturales distintas y sucesivas; se trata de mostrar lo que cada una de estas fases ha aportado a la construcción acumulativa del paisaje que se observa actualmente y de descifrar para cada una de ellas una concepción del paisaje diferente. La zona de estudio se encuadra dentro del área nuclear de los petro-(*) Grupo de Investigación en Arqueología del Paisaje, Universidade de Santiago de Compostela. Laboratorio de Arqueología, Edificio «Monte da Condesa», Campus Sur, Santiago (A Coruña=. pharpa@usc.es).El artículo fue remitido en su versión final el 17-VII-97. glifos galaicos de la Edad del Bronce, entre los ayuntamientos de Campo Lameiro y Cotobade (Pontevedra). Creemos que en ella se conservan elementos de su valor simbólico desde la Edad del Bronce hasta la Galicia tradicional. Lejos de proponer ningún tipo de persistencias seculares, nuestro análisis tratará de mostrar cómo cada uno de estos hitos se construye a partir de una concepción diferente del paisaje y cómo todas ellas, pese a esto, coinciden en remarcar una zona dotada de peculiares condiciones naturales, diferentemente interpretadas en cada momento. ABSTRACT This paper deals with the different models of landscapes found in the Prehistory

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Li-ion cells are one of the core components for the actual and future electric mobility. Differently from other types of applications and due to the high charge/discharge rates, the thermal-related issues in batteries for mobility are drastically relevant and can affect the reliability, the safety and the performance of the system. Indeed, limited temperature differences within a battery pack have a significant impact on its efficiency, thus it is important to predict and control the cell and battery pack temperature distribution. In the proposed study, a CFD analysis has been carried out to quantify the temperature and heat distribution on a single li-ion pouch cell. The main objective of this work is to determine the temperature imbalance on the cell and the required cooling load in order to be able to correctly design the cooling system and the best module architecture. The internal heat generation occurs as a result of electrochemical reactions taking place during charge and discharge of batteries. An electric model of the cell allows to assess the thermal power generation; the model parameters are changed according to the operative conditions to improve the accuracy, specifically to take into account varying temperature conditions and C-rates. The high accuracy of the model with respect to experimental data shows the potentiality of the proposed approach to support the optimization of Li-ion modules cooling systems and architecture design.

Computers in chemistry V 0380Modeling Oral Rat Chronic Toxicity. -(MAZZATORTA*, P.; ESTEVEZ, M. D.; COULET, M.; SCHILTER, B.; J. Chem. Inf. Model. (J. Chem. Inf. Comput. Sci.) 48 (2008) 10, 1949-1954; Qual. Saf. Dep., Nestle Res. Cent., CH-1000 Lausanne, Switz.; Eng.) -Lindner 04-213

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