Electrical imaging of soil water availability to grapevine: a benchmark experiment of several machine-learning techniques     

L.?BrillanteEmail authorView author&#;s OrcID profile  B.?Bois  O.?Mathieu  J.?Lévêque 《Precision Agriculture》2016,17(6):637-658

Electrical resistivity (ER) can be used to assess soil water in the field. This study investigated the possibility of extending the use of ER to measure plant available soil water variables, i.e. available soil water (ASW), total transpirable SW (TTSW), and fraction of transpirable SW (FTSW) using a pedotransfer approach. In a vineyard, 224 electrical resistivity tomography (ERT) transects and 672 time domain reflectometry (TDR) soil water profiles were acquired over 2 years. Soil physical–chemical properties were measured on 73 soil samples from eight different sites. To estimate the amount of soil water available to plants, grapevine (Vitis vinifera L.) water status was monitored by means of leaf water potentials. A benchmark experiment was carried out to compare four machine-learning techniques: multivariate adaptive regression splines (MARS), k-nearest neighbours (KNN), random forest (RF), and gradient boosting machine (GBM). Model interpretation led to a deeper understanding of the relationships between electrical resistivity and soil properties when predicting soil water availability for the plant. The models assessed had good predictive performance and were therefore used to map ASW, TTSW and FTSW in the vineyard. ER coupled to machine-learning algorithms was shown to be a good proxy for quantification and visualisation of plant available soil water with low disturbance.  相似文献   

Antiproliferative activity of violaxanthin isolated from bioguided fractionation of Dunaliella tertiolecta extracts     

Pasquet V  Morisset P  Ihammouine S  Chepied A  Aumailley L  Berard JB  Serive B  Kaas R  Lanneluc I  Thiery V  Lafferriere M  Piot JM  Patrice T  Cadoret JP  Picot L 《Marine drugs》2011,9(5):819-831

Dunaliella tertiolecta (DT) was chemically investigated to isolate molecules inhibiting cancer cell proliferation and inducing apoptosis in vitro. The potency to inhibit cell growth was used for the bio-guided fractionation and isolation of active compounds using chromatographic techniques. The DT dichloromethane extract exhibited a strong anti-proliferative activity on MCF-7 and LNCaP cells, and was further fractionated and sub-fractionated by RP-HPLC. High resolution mass spectrometry and spectrophotometric analysis unequivocally identified violaxanthin as the most antiproliferative molecule present in DT DCM extract. Violaxanthin purified from DT induced MCF-7 dose-dependent growth inhibition in continuous and discontinuous treatments, at concentrations as low as 0.1 μg·mL⁻¹ (0.17 μM). Phosphatidylserine exposure, typical of early apoptosis, was observed after 48 h treatment at 8 μg·mL⁻¹ (13.3 μM) but no DNA fragmentation, characteristic of late apoptosis steps, could be detected even after 72 h treatment at 40 μg·mL⁻¹ (66.7 μM). Taken together, our results demonstrate the strong antiproliferative activity of violaxanthin on one human mammary cancer cell line, and suggest that studying the pharmacology of violaxanthin and pharmacomodulated derivatives on cancer cells may allow potent antiproliferative drugs to be obtained.  相似文献   

Polymorphism Analysis of Microsatellites Associated with Seven Candidate Genes for Equine Cryptorchidism     

Mathieu Diribarne  Anne Vaiman  Michel Péchayre  E. Pailhoux  Xavier Mata  Gérard Guérin  Stéphane Chaffaux 《Journal of Equine Veterinary Science》2009

Association of seven candidate genes with cryptorchidism was investigated in the Thoroughbred. A pedigree composed of 23 cryptorchids and 24 nonaffected horses, sharing a common ancestor, was constituted. Sixteen microsatellite markers were developed either from bacterial artificial chromosomes (BAC) isolated for each candidate gene or by in silico screening. DNA from our pedigree was genotyped for these microsatellites. Statistical analysis of the allelic and genotypic frequencies observed with these markers did not reveal any association between the candidate genes and the cryptorchidism phenotype in our horse panel.  相似文献   

Modelling functional fish habitat connectivity in rivers: A case study for prioritizing restoration actions targeting brown trout          下载免费PDF全文

Mathieu L. Roy  Céline Le Pichon 《水产资源保护:海洋与淡水生态系统》2017,27(5):927-937

The reducing effect of aglime on N2O and CO2 emissions balance from an acidic soil: A study on intact soil cores     

Camille Rousset  Henri Brefort  Mustapha Arkoun  Olivier Mathieu  Catherine Hénault 《European Journal of Soil Science》2023,74(2):e13367

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