42 research outputs found
Direction-finding arrays of directional sensors for randomly located sources
The problem of directional sensor placement and orientation is considered when statistical information about the source direction of arrival is available. We focus on two-sensor arrays and form a cost function based on the Cramer-Rao bound that depends on the probability distribution of the coplanar source direction. Proper positioning and orientation of the sensors enable the two-sensor array to have an accuracy comparable to that of a three-or four-sensor uniform circular array
Analyse de la variabilitĂ© germinative de la vesce commune sous lâimpact dâun stress Ferrique-Cadmique-Salin
Ce travail a pour but de voir lâimpact de lâapplication dâune combinaison de stress abiotique sur la germination des graines de vesce commune ainsi que de visualiser les modifications physiologiques et histologiques au niveau des tissus racinaires sous lâinfluence de ces contraintes. De ce fait, une conduite de germination a Ă©tĂ© rĂ©alisĂ©e avec des graines de vesce commune dans diffĂ©rentes situations de combinaisons entre trois types de stress mĂ©tallique-cadmique-salin et un suivi a Ă©tĂ© fait en se basant sur des caractĂšres vĂ©gĂ©tatifs bien dĂ©terminĂ©s. Les rĂ©sultats montrent bien une nette diffĂ©rence entre les rĂ©ponses des graines Ă lâapplication de stress sĂ©parĂ©ment et entre les combinaisons de stress ainsi quâune variabilitĂ© intra-espĂšce Ă©norme vis-Ă -vis de diffĂ©rentes types de contraintes.Mots-clĂ©s : vesce commune, stress mĂ©tallique-cadmique-salin, caractĂšres vĂ©gĂ©tatifs, modifications physiologiques et histologiques
Relationship between epistasis and aggressiveness in resistance of pepper (Capsicum annuum L.) to Phytophthora nicotianae
This study evaluated the types of gene action governing the inheritance of resistance to Phytophthora nicotianae necrosis in populations derived from two crosses involving two susceptible (Beldi and Nabeul II) and one resistant (CM334) cultivars of pepper (Capsicum annuum L.). Populations, composed of Pr, Ps, F1 , F 2 , BC 1 Pr, and BC 1 Ps generations, were inoculated with six P. nicotianae isolates. Generation means analysis indicated that an additive-dominance model was appropriate for P. nicotianae isolates Pn Ko1 , Pn Ko2 and Pn Kr1 , which showed low aggressiveness in the two crosses. For the more aggressive isolates Pn Bz1 , Pn Bz2 and Pn Kr2 , epistasis was an integral component of resistance in the two crosses. The presence of epistasis in the resistance of pepper to P. nicotianae was dependent on the level of aggressiveness of the isolates. Selection in pepper with less aggressive isolates was efficient, but not with more aggressive isolates; on the other hand, selection with more aggressive isolates was more stable. The minimum number of genes controlling resistance was estimated at up to 2.71. In the majority of cases, the additive variance was significant and greater than the environmental and dominance variance
Epistasis and genotype-by-environment interaction of grain protein content in durum wheat
Parental, F1 , F 2 , BC 1 and BC 2 generations of four crosses involving four cultivars of durum wheat (Triticum durum Desf.) were evaluated at two sites in Tunisia. A three-parameter model was found inadequate for all cases except crosses Chili x Cocorit 71 at site Sidi Thabet and Inrat 69 x Karim at both sites. In most cases a digenic epistatic model was sufficient to explain variation in generation means. Dominance effects (h) and additive x additive epistasis (i) (when significant) were more important than additive (d) effects and other epistatic components. Considering the genotype-by-environment interaction, the non-interactive model (m, d, h, e) was found adequate. Additive variance was higher than environmental variance in three crosses at both sites. The estimated values of narrow-sense heritability were dependent upon the cross and the sites and were 0%-85%. The results indicate that appropriate choice of environment and selection in later generations would increase grain protein content in durum wheat
Osimertinib benefit in EGFR-mutant NSCLC patients with T790M-mutation detected by circulating tumour DNA
BACKGROUND: Approximately 50% of Epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC) patients treated with EGFR tyrosine kinase inhibitors (TKIs) will acquire resistance by the T790M mutation. Osimertinib is the standard of care in this situation. The present study assesses the efficacy of osimertinib when T790M status is determined in circulating cell-free tumour DNA (ctDNA) from blood samples in progressing advanced EGFR-mutant NSCLC patients. MATERIAL AND METHODS: ctDNA T790M mutational status was assessed by Inivata InVision(TM) (eTAm-Seq(TM)) assay in 48 EGFR-mutant advanced NSCLC patients with acquired resistance to EGFR TKIs without a tissue biopsy between April 2015 and April 2016. Progressing T790M-positive NSCLC patients received osimertinib (80âmg daily). The objectives were to assess the response rate to osimertinib according to Response Evaluation Criteria in Solid Tumours (RECIST) 1.1, the progression-free survival (PFS) on osimertinib, and the percentage of T790M positive in ctDNA. RESULTS: The ctDNA T790M mutation was detected in 50% of NSCLC patients. Among evaluable patients osimertinib gave a partial response rate of 62.5% and a stable disease rate of 37.5%. All responses were confirmed responses. After median follow up of 8 months, median PFS by RECIST criteria was not achieved (95% CI: 4-NA), with 6- and 12-months PFS of 66.7% and 52%, respectively. CONCLUSIONS: ctDNA from liquid biopsy can be used as a surrogate marker for T790M in tumour tissue
Effects of tegument, endosperm, cold treatment and harvest date on germination of wild olive
Wildolive seeds (Olea europaea L. var. sylvestris), calledoleaster do not germinate when placedunder
favourable conditions. In a series of experiments the effects of the harvest date, the endosperm, the tegument,
andthe coldtreatment were evaluatedon germination of seeds andembryos. The germination percentage
of embryos and seeds harvested at different harvest dates increased during October month, these percentages
decreased during November month, whereas no seeds and embryos harvested on the middle of December
germinated. Embryo germinability was always higher than seed germinability, and this may be due to an
inhibiting effect of the teguments and the endosperm on seed germination. Such dormancy, which gradually
increased during maturation, could reside mainly in the endosperm and partly within the embryo. The cold
treatment at 4°C for four to thirteen days increased seed and embryo germinability, whereas lengthening time
at this temperature showeda negative effect on seedgermination. The germination of seeds andembryos
from six wildolive trees was also examinedby recording the germination percentage andminimum imbibition
time (Tmi)
Augmented Skeletal Joints for Temporal Segmentation of Sign Language Actions
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