Association among quantitative, chromosomal and enzymatic traits in a natural population of Drosophila melanogaster

International audienc

Color image segmentation using perceptual spaces through applets for determining and preventing diseases in chili peppers

Plant pathogens cause disease in plants. Chili peppers are one of the most important crops in the world. There are currently disease detection techniques classified as: biochemical, microscopy, immunology, nucleic acid hybridization, identification by visual inspection in vitro or in situ but these have the following disadvantages: they require several days, their implementation is costly and highly trained. This paper proposes a method for knowing and preventing the disease in chili peppers plant through a color image processing, using online system developed in Java applets. This system gets results in real time and remotely (Internet). The images are converted to perceptual spaces [hue, saturation and lightness (HSL), hue, saturation, and intensity (HSI) and hue saturation and value (HSV)]. Sequence was applied to the proposed method. HSI color space was the best detected disease. The percentage of disease in the leaf is of 12.42%. HSL and HSV do not expose the exact area of the disease compared to the HSI color space. Finally, images were analyzed and the disease is known by the expert in plant pathology to take preventive or corrective actions.Keywords: Applets, knowing disease, color image segmentation, perceptual spacesAfrican Journal of Biotechnology Vol. 12(7), pp. 679-68

Biological activity of Ipomoea pauciflora Martens and Galeotti (Convolvulaceae) extracts and fractions on larvae of Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae)

Hexane, chloroform and methanol extracts of different parts of Ipomoea pauciflora were tested for their effects on the survival and development of Fall Armyworm (Spodoptera frugiperda), a Lepidoptera pest. For seven days, neonatal larvae (grown at 27 ± 2°C with a 16: 8 (L: D) h photoperiod) were exposed to different concentrations of crude I. pauciflora extracts (ranging from 0 to 4 mg/ml) that were incorporated into an artificial diet. Surviving larvae were weighed at days 6, 9 and 13 and were maintained until moths emerged. Eleven of the 18 crude extracts showed more than 30% larval mortality. The highest mortality was produced by hexane and chloroform extracts of seeds at 4 mg/ml(96.9 and 93.8%, respectively), with LC50 values of 1.85 mg/ml and 0.54 mg/ml, respectively. Fractions of both seed extracts were isolated by gravity column chromatography over silica gel and analyzed for their active compounds. Eight fractions of the hexane extract and six fractions of the chloroform extract from I. pauciflora seeds, exhibited larvicidal effects at 1 mg/ml (mortality from 33.3 to 88.9% and from 47.2 to 77%, respectively). Changes in larval weight were observed as compared with the control group. Phytochemical analysis through GC-MS and H1 NMR revealed the presence of fatty acids and aldehydes in the active fractions. These results indicate that the bioactive extracts from the seed of I. pauciflora can induce lethal toxicity in S. frugiperda larvae or affect the weight of the surviving larvae

Metabolic profiling of sourdough fermented wheat and rye bread

Sourdough fermentation by lactic acid bacteria is commonly used in bread baking, affecting several attributes of the final product. We analyzed whole-grain wheat and rye breads and doughs prepared with baker's yeast or a sourdough starter including Candida milleri, Lactobacillus brevis and Lactobacillus plantarum using non-targeted metabolic profiling utilizing LC-QTOF-MS. The aim was to determine the fermentation-induced changes in metabolites potentially contributing to the health-promoting properties of whole-grain wheat and rye. Overall, we identified 118 compounds with significantly increased levels in sourdough, including branched-chain amino acids (BCAAs) and their metabolites, small peptides with high proportion of BCAAs, microbial metabolites of phenolic acids and several other potentially bioactive compounds. We also identified 69 compounds with significantly decreased levels, including phenolic acid precursors, nucleosides, and nucleobases. Intensive sourdough fermentation had a higher impact on the metabolite profile of whole-grain rye compared to milder whole-grain wheat sourdough fermentation. We hypothesize that the increased amount of BCAAs and potentially bioactive small peptides may contribute to the insulin response of rye bread, and in more general, the overall protective effect against T2DM and CVD.Peer reviewe

The Submarine Volcano Eruption off El Hierro Island: Effects on the Scattering Migrant Biota and the Evolution of the Pelagic Communities

Versión del editor

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT