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The aim of this study is the extraction and the identification of volatile organic compounds (VOCs) and total phenolic compounds of three Opuntia ficus-indica (L.) Mill., species from Morocco, namely Dellahia, Aissa and Shoul. The VOCs were extracted with Solid-Phase Microextraction (SPME) associated to gas chromatography-mass spectrometry (GC-MS) analysis. The antioxidant compounds in extracts were determined by liquid- Chromatography-Mass Spectrometry (LC-MS). The study allowed the identification of forty-six compounds for the VOCs. The most abundant compounds in the three varieties (Dellahia, Aissa and Shoul) were 2-hexanal and n-hexanol with a percentage of 10.6%, 10.9% and 44.0% for the first compound and 10.3 %, 59.0%, 18.7% for the second, successively. The extraction of phenolic compounds permitted the identification and quantification of 15 fractions of flavonoids and phenolic acids. Caffeic acid was the most abundant phenolic acid with 16.0 and 10.8 mg/100g of plant material respectively for Dellahia and Aissa. For flavoinoids composition, isorhamnetin was the major compound. It accounted respectively for 40.5% and 43.2% for Dellahia and Aissa. We can conclude that cactus pear fruits are a good source of natural antioxidants and the major compounds responsible of flavor in the studied varieties are 2-hexanal and n-hexanol.

This paper is aimed at investigating the benefits in terms of energy efficiency of new electro-hydraulic architectures for power distribution systems of a medium-size agricultural tractor, with a focus on the hydraulic high-pressure circuit. The work is part of a wider industrial research project called TASC (Smart and Clean Agricultural Tractors [1]). Traditional and alternative architectures have been modelled and energetically compared through simulation, using a lumped parameter approach. Experimental data previously acquired have been used to validate the models and to replicate real working conditions of the machine in the simulation environment. A typical on-field manoeuvre has been used as duty cycle, to perform an effective energetic analysis. The standard hydraulic circuit is a multi-users load sensing system that uses a single variable displacement pump to feed steering, trailer brake and auxiliary utilities in that order. The key idea of the proposed solutions is the separation of steering from the other implements, to optimize the entire energy management. In particular, the paper investigates new and flexible solutions for the auxiliary utilities, including an electro-hydraulic load sensing architecture with variable pump margin, an electronic flow matching and flow sharing architecture, and an electronic strategy for automatic pressure compensation. The simulation results show that good energy saving can be achieved with the alternative architectures, so that physical prototyping of the most promising solutions will be realized as next step of the project.

Increasing interest in reducing pollutant emissions and fuel consumption of off-road vehicles has led to research alternative systems that aim to reduce the power dissipations of the hydraulic circuits. This work presents the advantages of few alternative solutions for a hydraulic high-pressure circuit of a medium-size tractor. The standard high-pressure circuit is a typical multiusers load sensing system that uses a single variable displacement pump to feed: steering, trailer brake, rear remotes, hitch and suspension. The alternative architectures have been simulated and compared in terms of mechanical energy consumption. In particular, the steering has been separated from the circuit, it has been actuated by means of a dedicated pump moved by an electric motor, in this way the priority valve could be removed and losses due the pressure compensators are reduced. A further architecture based on the insertion of the LS signal conditioner was studied. The results show that relevant energy saving can be achieved with the new alternative architectures; the physical prototyping of the most promising solutions will be realized as the next step of the project.

In this study, we suggest a method adapted to the retrodeformation of asymmetrical objects - such as limb bones - by quantitatively estimating the effectiveness of the Thin-Plate Splines (TPS) interpolation function as a retrodeformation tool. To do so, taphonomic deformations were first simulated on a single horse femur. The original bone was then used as a reference in order to drive the retrodeformation using anatomical landmarks. This approach, based on a single bone, enabled us to evaluate the performance of the retrodeformation procedure. Then, the same approach was performed on a sample of rhino femora but using a different specimen (from the same species) as the reference in order to account for morphological variation. We also added sliding semi-landmarks on anatomical curves. Finally, retrodeformation was applied on a sample of sauropodomorph dinosaur femora by building a mean shape based on several well-preserved fossil specimens. Results show that entirely flattened and stretched bones are more efficiently retrodeformed than bent and twisted bones. Introduction of morphological variation increased the efficiency of retrodeformation for bent and locally stretched bones. The application to the sample of fossils produced similar results but also highlighted the difficulty of retrodeforming bones with a combination of different deformations. TPS interpolation is an efficient tool of retrodeformation for asymmetrical objects, especially for bones with only one affine deformation such as flattening or stretching. Finding a threshold of landmark number to use for this process would be the next step because it would allow us to ensure the quality of retrodeformation while keeping available a reasonable number of landmarks in order to perform shape analysis on retrodeformed bones. Twisted and bent fossils are frequently discovered and we suggest that these kinds of deformations should be studied with caution, especially when combined with other types of taphonomic distortions. [ABSTRACT FROM AUTHOR]