Detection of Heterodera avenae infestations on winter wheat by radiothermometry

International audienc

Bare soil moisture retrieval from multi-temporal X-band TerraSAR-X SAR images

IGARSS 2015, Milan, ITA, 26-/07/2015 - 31/07/2015International audienceThe aim of the present study is to analyze the sensitivity of X-band SAR (TerraSAR-X) signals as a function of different physical bare soil parameters (soil moisture, soil roughness), and to evaluate the accuracy of change detection approach proposed for soil moisture estimation. Firstly, we presented a brief description of our ground and satellite database. Secondly, we considered the main results of our statistical analysis of the relationships between radar and soil parameters: soil moisture and different roughness parameters (the rms height, Zs parameter, and a new roughness parameter Zg. Finally, we proposed an algorithm combing multi-temporal X-band SAR images (TerraSAR-X) with different continuous thetaprobe measurements for the retrieval of surface soil moisture at a high spatial resolution

Vertex labeling and routing in expanded Apollonian networks

We present a family of networks, expanded deterministic Apollonian networks, which are a generalization of the Apollonian networks and are simultaneously scale-free, small-world, and highly clustered. We introduce a labeling of their vertices that allows to determine a shortest path routing between any two vertices of the network based only on the labels.Comment: 16 pages, 2 figure

High Dimensional Apollonian Networks

We propose a simple algorithm which produces high dimensional Apollonian networks with both small-world and scale-free characteristics. We derive analytical expressions for the degree distribution, the clustering coefficient and the diameter of the networks, which are determined by their dimension

Influence of Radar Frequency on the Relationship Between Bare Surface Soil Moisture Vertical Profile and Radar Backscatter

International audienceThe aim of this letter is to discuss the influence of radar frequency on the relationship between surface soil moisture and the nature of radar backscatter over bare soils. In an attempt to address this issue, the advanced integral equation model was used to simulate backscatter from soil surfaces with various moisture vertical profiles, for three frequency bands, namely, L, C, and X. In these computations, we investigated the influence of the vertical heterogeneity of soil moisture on the characteristics of the backscattered signals. The influence of radar frequency is clearly demonstrated. A database produced from Envisat ASAR and TerraSAR-X data, which was acquired over bare soils with in situ measurements of moisture content and ground surface roughness, was used to validate the utility of taking the soil moisture heterogeneity into account in the backscatter model

Isolation and molecular characterization of RcSERK1: A Rosa canina gene transcriptionally induced during initiation of protocorm-like bodies

A somatic embryogensis receptor-like kinase (SERK) gene was isolated from protocorm-like bodies (PLBs) of Rosa canina by a rapid amplification of cDNA ends (RACE) approach and was designated as RcSERK1. The RcSERK1 encodes a protein of 626 amino acid residues with a calculated molecular mass of 68.79 kDa and theoretical isoelectric point of 5.65. The amino acid sequence of RcSERK1 shares all the characteristic features of a SERK protein, including the signal peptide (SP), the leucine zipper (LZ), the five leucine-rich repeats (LRRs), the pro-rich domain containing the so-called Ser-Pro- Pro (SPP) motif, the transmembrane domain (TM), the kinase domain and the C-terminal domain. The transcripts of RcSERK1 were more enriched in PLBs than in rhizoids and callus, but not detected in leaflets (incubated under dark and before producing callus) and the regenerated shoots. Subcellular localization indicated that the fluorescence of RcSERK1-GFP was recorded in the plasma membrane. We argue that RcSERK1 is a Leu-rich repeat receptor-like kinase (LRR-RLK) and plasma  membrane localization protein.Keywords: somatic embryogensis receptor-like kinase (SERK)1, protocorm-like bodies (PLBs), Rosa canina, RACE, RcSERK1

Evolution of the vegetation cover in Ichkeul National Park (Tunisia)

Ichkeul wetland ecosystems are characterized by hygrophile vegetation. This later requires to be submerged by fresh water during a period of the year in order to fullfi l its vegetative cycle. Hydrologic constructions and dry years infl uence the evolution of wetland vegetation distribution in Ichkeul National Park. To follow up this evolution, we mapped the vegetation in 1994 and 2002. The analysis of all existing data concerning Ichkeul wetland vegetation since 1967 and our surveys between 1994 and 2005 allowed us to understand the evolution of wetland vegetation distribution and explain it. Until 2002, ecosystems suffered from intense salinisation, the drying-up showed by development of halophilous vegetation and the extension of occasionally inundated areas. At the beginning of the year 2003, fresh water infl ows were generated by exceptional rains and entered the park, provoking water stagnation during more than two months in Ichkeul marshes. These conditions led to a regression of the halophilous vegetation and its replacement by an hygrophilous one, based on sedges, rushes,... Ichkeul wetland ecosystems showed a good resilience: one year was suffi cient to regenerate hygrophilous vegetation after 15 years of water shortageLes écosysternes lagunaires de l'Ichkeul sont caractérisés par une végétation hygrophile exigeant la submersion en eau douce pendant une période de l'année pour accomplir leur cycle végétatif. Les constructions hydrologiques et les années de sécheresses influencent l'évolution et la répartition de la végétation des marais du Parc national de l'Ichkeul. Pour suivre cette évolution, nous avons cartographié la végétation en 1994 et 2002. L'analyse des données publiées au sujet de la végétation des marais de l'Ichkeul depuis 1967 et de nos observations réalisées entre 1994 et 2005 nous a permis de comprendre l'évolution de la répartition de la végétation des marais et de l'expliquer. Jusqu'en 2002, les écosystèmes ont souffert d'une salinisation et d'une sécheresse intenses qui se sont traduites par le développement d'une végétation halophile et la réduction des superficies inondables. Au début de l'année 2003, des apports d'eau douce ont été produits par les pluies exceptionnelles et ont alimenté le parc, provoquant la stagnation de l'eau durant plus de deux mois dans les marais de l'Ichkeul. Ces conditions ont provoqué une dégradation de la végétation halophile au profit de la régénération de la végétation hygrophile à base de scirpes, de joncs, de carex... Les écosystèmes lagunaires de l'Ichkeul ont fait preuve d'une bonne résilience : une année favorable s'est avérée suffisante pour régénérer la végétation hygrophile après 15 ans de manque d'eau

Analysis of soil texture using terrasar x-band sar

International audienceIn this paper, it is proposed to use TERRASAR-X data for analysis and estimation of soil surface texture. Our study is based on experimental campaigns carried out over a semi-arid area in North Africa. Simultaneously to TERRASAR-X radar acquisitions, ground measurements (texture, soil moisture and roughness) were made on different test fields. A strong correlation is observed between soil texture and a processed signal from two radar images, the first acquired just after a rain event and the second corresponding to dry soil conditions, acquired three weeks later. An empirical relationship is proposed for the retrieval from radar signals of clay content percent. Soil texture mapping is proposed over the study site, which includes bare soils and olive groves

PBRM1 acts as a p53 lysine-acetylation reader to suppress renal tumor growth.

p53 acetylation is indispensable for its transcriptional activity and tumor suppressive function. However, the identity of reader protein(s) for p53 acetylation remains elusive. PBRM1, the second most highly mutated tumor suppressor gene in kidney cancer, encodes PBRM1. Here, we identify PBRM1 as a reader for p53 acetylation on lysine 382 (K382Ac) through its bromodomain 4 (BD4). Notably, mutations on key residues of BD4 disrupt recognition of p53 K382Ac. The mutation in BD4 also reduces p53 binding to promoters of target genes such as CDKN1A (p21). Consequently, the PBRM1 BD4 mutant fails to fully support p53 transcriptional activity and is defective as a tumor suppressor. We also find that expressions of PBRM1 and p21 correlate with each other in human kidney cancer samples. Our findings uncover a tumor suppressive mechanism of PBRM1 in kidney cancer and provide a mechanistic insight into the crosstalk between p53 and SWI/SNF complexes