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111.
Petrović Andjeljko Pérez Hidalgo Nicolas Michelena Saval José Manuel Tomanović Željko 《Phytoparasitica》2021,49(1):93-101
Phytoparasitica - Here we describe Aphidius erodii sp. n. associated with Acyrthosiphon malvae (Mosley, 1841), which is a pest on herbaceous ornamental Geranium and Pelargonium plants, but also an... 相似文献
112.
Cambou Aurélie Saby Nicolas P.A. Hunault Gilles Nold François Cannavo Patrice Schwartz Christophe Vidal-Beaudet Laure 《Journal of Soils and Sediments》2021,21(2):1038-1052
Journal of Soils and Sediments - Assessments of urban soil organic carbon stock (SOCS) are scant because citywide data are scarce. Moreover, we do not know which factors mostly explain SOCS spatial... 相似文献
113.
Prediction of internal bond strength in a medium density fiberboard process using multivariate statistical methods and variable selection 总被引:2,自引:1,他引:1
Nicolas André Hyun-Woo Cho Seung Hyun Baek Myong-Kee Jeong Timothy M. Young 《Wood Science and Technology》2008,42(7):521-534
This paper presents new data mining-based multivariate calibration models for predicting internal bond strength from medium
density fiberboard (MDF) process variables. It utilizes genetic algorithms (GA) based variable selection combined with several
calibration methods. By adopting a proper variable selection scheme, the prediction performance can be improved because of
the exclusion of non-informative variable(s). A case study using real plant data showed that the calibration models based
on the process variables selected by GA produced better performance than those without variable selection, with the exception
of the radial basis function (RBF) neural networks model. In particular, the calibration model based on supervised probabilistic
principal component analysis (SPPCA) yielded better performance (only when using GA) than partial least squares (PLS), orthogonal-PLS
(O-PLS), and radial basis function neural networks models. The SPPCA model benefits most from the use of GA-based variable
selection in this case study.
N. André and H.-W. Cho equally contributed to this work. 相似文献
114.
Nicolas Tremblay Zhijie Wang Bao-Luo Ma Carl Belec Philippe Vigneault 《Precision Agriculture》2009,10(2):145-161
Nitrogen (N) fertilizer rates applied spatially according to crop requirements can improve the efficiency of N use. The study
compares the performance of two commercial sensors, the Yara N-Sensor/FieldScan (Yara International ASA, Germany) and the
GreenSeeker (NTech Industries Inc., Ukiah, California, USA), for assessing the status of N in spring wheat (Triticum aestivum L.) and corn (Zea mays L.). Four experiments were conducted at different locations in Quebec and Ontario, Canada. The normalized difference vegetation
index (NDVI) was determined with the two sensors at specific growth stages. The NDVI values derived from Yara N-Sensor/FieldScan
correlated with those from GreenSeeker, but only at the early growth stages, where the NDVI values varied from 0.2 to 0.6.
Both sensors were capable of describing the N condition of the crop or variation in the stand, but each sensor had its own
sensitivity characteristics. It follows that the algorithms developed with one sensor for variable-rate N application cannot
be transferred directly to another sensor. The Yara N-Sensor/FieldScan views the crop at an oblique angle over the rows and
detects more biomass per unit of soil surface compared to the GreenSeeker with its nadir (top-down) view of the crop. The
Yara N-Sensor/FieldScan should be used before growth stage V5 for corn during the season if NDVI is used to derive crop N
requirements. GreenSeeker performed well where NDVI values were >0.5. However, unlike GreenSeeker, the Yara N-Sensor/FieldScan
can also record spectral information from wavebands other than red and near infrared, and more vegetation indices can be derived
that might relate better to N status than NDVI. 相似文献
115.
In many countries, including the European Union member states, Switzerland, Australia, New Zealand, and Japan, legislation has been set up for labeling of genetically modified organisms (GMOs) in food and feed products. To comply with these regulations, reliable detection methods are necessary. If the detection is based on DNA, a GMO analysis may contain several steps where qualitative and quantitative species-specific, GMO screening, GMO construct, and GMO line-specific polymerase chain reactions (PCRs) are used. A limit of detection (LOD) thereby defines to what extent a target molecule may be detected in a sample. In this study, cookies were made with variable levels of a soy sample containing 2 wt% Roundup Ready soy. For all PCRs described, detection limits based on dilution series and practical LODs were determined. The practical LODs are used to determine to what extent a GMO ingredient may be detected in a real food product. Results reveal that, due to the baking process, the overall DNA fragment length is reduced, rendering GMO analyses more difficult. Furthermore, Roundup Ready soy line-specific and real-time quantitative PCR are less sensitive than GMO screening PCRs, whereas just these PCRs are crucial in the decision-making process regarding the presence of GMOs in a food product. Moreover, high standard deviations and errors render the precise quantification of GMOs difficult. 相似文献
116.
ABSTRACT European stone fruit yellows (ESFY) is becoming a major economic problem for Prunus growers in Europe. The causal agent ("Candidatus Phytoplasma prunorum") and its vector (Cacopsylla pruni) have been identified, but the present knowledge of the risk factors for this disease relies, at best, on specific experiments. To assess the relative significance of several factors correlated with ESFY incidence in the field, an exhaustive survey was performed on apricot and Japanese plum orchards in the Crau plain (France). After a preliminary multivariate exploration of the data, we used a logistic regression model to analyze and predict the cumulative number of diseased trees on the basis of a set of quantitative (age, planting density, and area of the orchard) and categorical variables (species, cultivar, and rootstock). Because of the nature of the data, we used an overdispersed binomial model and we developed a parametric bootstrap procedure based on the beta-binomial distribution to obtain confidence intervals. Our results indicated that the age, species, and cultivar of the scion were the major factors explaining the observed number of diseased trees. The planting density and the rootstocks used in the zone under study were less significant, and the area of the orchard had no effect. The residuals of the model showed that some explanatory variables had not been taken into account, because part of the remaining variability could be explained by a grower effect. The spatial distribution of the residuals suggested that one of the reasons for this grower effect was the correlation between orchards closer than 100 m, possibly caused by the flight behavior of infectious vectors. 相似文献
117.
Christelle Simon-Colin Yannick Gueguen Evelyne Bachere Achraf Kouzayha Denis Saulnier Nicolas Gayet Jean Guezennec 《Marine drugs》2015,13(6):3732-3744
Cultured pearls are the product of grafting and rearing of Pinctada margaritifera pearl oysters in their natural environment. Nucleus rejections and oyster mortality appear to result from bacterial infections or from an inappropriate grafting practice. To reduce the impact of bacterial infections, synthetic antibiotics have been applied during the grafting practice. However, the use of such antibiotics presents a number of problems associated with their incomplete biodegradability, limited efficacy in some cases, and an increased risk of selecting for antimicrobial resistant bacteria. We investigated the application of a marine antimicrobial peptide, tachyplesin, which is present in the Japanese horseshoe crab Tachypleus tridentatus, in combination with two marine bacterial exopolymers as alternative treatment agents. In field studies, the combination treatment resulted in a significant reduction in graft failures vs. untreated controls. The combination of tachyplesin (73 mg/L) with two bacterial exopolysaccharides (0.5% w/w) acting as filming agents, reduces graft-associated bacterial contamination. The survival data were similar to that reported for antibiotic treatments. These data suggest that non-antibiotic treatments of pearl oysters may provide an effective means of improving oyster survival following grafting procedures. 相似文献
118.
Macaire Dobo Nicolas Ayres Grace Walker Williams D. Park 《Journal of Cereal Science》2010,52(3):450-456
The present study was conducted to investigate the relationship between waxy allelic forms and amylose in European and US rice germplasm. These allelic forms were defined according to the single-nucleotide polymorphisms (SNP) found in the leader intron 5′ splice site (G → T), exon 6 (A → C) and exon 10 (C → T). The combination of these three SNPs accounted for 89.2% of the variation in apparent amylose content in a pedigree of 85 US rice varieties and 93.8% of the variation among 279 accessions in a European germplasm collection. The allelic forms TAC and TCC were found in low amylose varieties. All varieties with intermediate levels of apparent amylose had the GCC allele. High levels of apparent amylose varieties had either the GAT and GAC allele. The sequence AGTTATA in the intron 1 distinguished the low amylose varieties from the other classes regardless of any other base changes. Intermediate amylose varieties can be distinguished from those with high apparent amylose by changes in either exon 6 or exon 10. However the simplest interpretation of the data is that the tyrosine/serine change in exon 6 is responsible for the lower levels of Granule bound starch synthase (GBSS) protein and thus lower levels of amylose in intermediate vs. high amylose verities. 相似文献
119.
Mathieu Jonard Frédéric André François Jonard Nicolas Mouton Pierre Procès Quentin Ponette 《Annals of Forest Science》2007,64(2):141-150
Total Soil Respiration (TSR) was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique: Mineral Soil Respiration (MSR) and Forest Floor Respiration (FFR). In addition, laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q 10 functions. In situ, significant differences (α = 0,05) between stands were observed for the R 10 parameter (respiration rate at 10 °C) of the TSR, MSR and FFR contributions, while only the temperature sensitivity (Q 10) of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions, the R 10 of the forest floor and of the Ah horizon varied with stand composition and the Q 10 of the forest floor decreased in the order: oak (2.27) > mixture (2.01) > beech (1.71). 相似文献
120.
A map of the interactome network of the metazoan C. elegans 总被引:1,自引:0,他引:1
Li S Armstrong CM Bertin N Ge H Milstein S Boxem M Vidalain PO Han JD Chesneau A Hao T Goldberg DS Li N Martinez M Rual JF Lamesch P Xu L Tewari M Wong SL Zhang LV Berriz GF Jacotot L Vaglio P Reboul J Hirozane-Kishikawa T Li Q Gabel HW Elewa A Baumgartner B Rose DJ Yu H Bosak S Sequerra R Fraser A Mango SE Saxton WM Strome S Van Den Heuvel S Piano F Vandenhaute J Sardet C Gerstein M Doucette-Stamm L Gunsalus KC Harper JW Cusick ME Roth FP Hill DE Vidal M 《Science (New York, N.Y.)》2004,303(5657):540-543