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Metadata only record Within the last thirty years in the West African Sahel, farmers have started to implement agroenvironmental practices which have allowed them to improve the soil quality and increase crop yields. Using two examples of land rehabilitation in Africa, this paper examines the technical and institutional innovations and their impacts on the ability to meet food demand for the growing population. Agroenvironmental techniques incorporate trees into the agricultural landscape, which improves water retention in the soil, increases the supply of nutrients, reduces wind erosion, and provides other marketable tree products. This large-scale effort has created income opportunities for farmers, benefited women, and increased food supply for many African families.

AbstractCalorimetry and other on‐line techniques are used for the first time as complement to the traditional off‐line methods in order to follow the growth of the green Chlorella vulgaris microalgae. A 2‐L photo‐bio‐reactor was adapted from a commercial calorimeter used previously to study heterotrophic microbial growth. An external source of light was added to favor the photosynthesis of the autotrophic cells. Heterotrophic growth was also tested with external glucose in the broth. A third mode, mixotrophic, allowed faster autotrophic plus heterotrophic growth. Calorimetric measurements were performed considering the corresponding calibrations in order to consider only the energy involved during the microalgal growth. The three different modes of Chlorella cultures were energetically characterized. Besides calorimetry, the weight of diluted nitric acid added to maintain the pH of the culture was correlated with the cellular growth and the nitrogen composition of the algae. Additionally, the on‐line infrared spectroscopy proved to be an efficient technique to follow the composition of the broth in glucose, nitrates, and phosphates. These results were compared and complemented with some classic off‐line techniques used to track this kind of cultures. Biotechnol. Bioeng. 2007;96:757–767. © 2006 Wiley Periodicals, Inc.

Abstract In the present work, the hygrothermal behavior of a wall structure made of a novel biobased material, i.e. date palm fiber reinforced concrete was investigated. In this context, a specific setup was developed which allows simulating a bi-climatic environment with separate outdoor and indoor environments. This device made it possible to apply various scenarios of static / dynamic hygrothermal loading to the outer side of wall, involving variation/cycling of temperature (T) and /or relative humidity (RH). During these experiments, resulting variations of T and RH across the wall thickness were monitored with in-situ sensors. Outstanding thermo-hygric phenomena were highlighted, such as high coupling effect between heat and moisture transfers, resulting from evaporation-condensation and sorption-desorption processes. Besides, significant thermal and hygric inertia was observed through the Date Palme Concrete (DPC) wall. The response time of this DPC wall to temperature variations remains shorter than in the case of humidity variations. Even so, large damping effect is obtained compared to outdoor boundary conditions, which make this DPC wall a good candidate for mitigating overheating during summertime and reducing interstitial condensation as well.

The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data- taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7.6 million cosmic-ray events, collected using a tracking trigger and reconstructed with modular pattern-recognition and fitting software. The intrinsic hit efficiency and tracking trigger efficiencies are close to 100%. Lorentz angle measurements for both electrons and holes, specific energy-loss calibration and transition radiation turn-on measurements have been performed. Different alignment techniques have been used to reconstruct the detector geometry. After the initial alignment, a transverse impact parameter resolution of 22.1+/-0.9 ��m and a relative momentum resolution ��p/p = (4.83+/-0.16) \times 10-4 GeV-1 \times pT have been measured for high momentum tracks. 34 pages, 25 figures