Cassava genome from a wild ancestor to cultivated varieties

Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology

A multifunctional device as both strain sensor and energy harvester for structural health monitoring

International audienceIn the context of wireless sensors (WSs) autonomous in energy, this paper presents a single macro-fiber composite (MFC) piezoelectric transducer which is used for the first time as a multifunctional device as both sensor and energy harvester in a time-multiplexing manner. The MFC is used as an energy harvester to charge up a storage capacitor. When there is sufficient energy, the WS is powered up and the MFC is used as a sensor. A circuit was implemented to harvest energy from the MFC and use the MFC as a sensor. Experiment validation shows that the MFC has an accuracy of up to 97 % as sensor and the circuit harvests energy from the MFC at its maximum power point with up to 98 % efficiency

Preparation of mesoporous titania film using nonionic triblock copolymer as surfactant template

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Single piezoelectric transducer as strain sensor and energy harvester using time-multiplexing operation

International audienceThis paper presents the implementation of a single piece of macro-fiber composite (MFC) piezoelectric transducer as a multifunctional device for both strain sensing and energy harvesting for the first time in the context of an energy harvesting powered wireless sensing system. The multifunction device is achieved via time-multiplexing operation for alternating dynamic strain sensing and energy harvesting functions at different time slots associated with different energy levels, that is, when there is insufficient energy harvested in the energy storage for powering the system, the MFC is used as an energy harvester for charging up the storage capacitor; otherwise, the harvested energy is used for powering the system and the MFC is used as a strain sensor for measuring dynamic structural strain. A circuit is designed and implemented to manage the single piece of MFC as the multifunctional device in a time-multiplexing manner, and the operation is validated by the experimental results. The dynamic strains measured by the MFC in the implemented system match a commercial strain sensor of extensometer by 95.5 to 99.99 %, and thus the studied method can be used for autonomous structural health monitoring of dynamic strain

Bioactive Constituents from the Whole Plants of Gentianella acuta (Michx.) Hulten

As a Mongolian native medicine and Ewenki folk medicinal plant, Gentianella acuta has been widely used for the treatment of diarrhea, hepatitis, arrhythmia, and coronary heart disease. In the course of investigating efficacy compounds to treat diarrhea using a mouse isolated intestine tissue model, we found 70% EtOH extract of G. acuta whole plants had an inhibitory effect on intestine contraction tension. Here, nineteen constituents, including five new compounds, named as gentiiridosides A (1), B (2), gentilignanoside A (3), (1R)-2,2,3-trimethyl-4-hydroxymethylcyclopent-3-ene-1-methyl-O-β-d-glucopyranoside (4), and (3Z)-3-hexene-1,5-diol 1-O-α-l-arabinopyranosyl(1→6)-β-d-glucopyranoside (5) were obtained from it. The structures of them were elucidated by chemical and spectroscopic methods. Furthermore, the inhibitory effects on motility of mouse isolated intestine tissue of the above mentioned compounds and other thirteen iridoid- and secoiridoid-type monoterpenes (7–10, 13–16, 18, 19, 21, 22, and 25) previously obtained in the plant were analyzed. As results, new compound 5, some secoiridoid-type monoterpenes 7, 10, 12–14, 16, and 17, as well as 7-O-9′-type lignans 31 and 32 displayed significant inhibitory effect on contraction tension at 40 μM