Integrative taxonomy of a key weevil pest in South Africa (Phlyctinus callosus Boh.) reveals a complex of at least six species

Phlyctinus callosus Boheman, 1934 (Curculionidae, Entiminae, Oosomini) is a species native from the Western Cape Province of South Africa. This pest causes economic damage to deciduous fruit during the adult stage and its quarantine status is strongly affecting fruit export markets. In addition to the damage caused within the country, it has spread to several areas of the Southern hemisphere via human mediated transportation. Phlyctinus callosus is presently considered as the only species of the genus Phlyctinus, however, slight morphological variation and the sporadic nature of this pest raised doubts on the present taxonomic status of this species. We applied an integrative taxonomic approach, combining the examination of external and internal morphological characters of adults and DNA sequencing (COI) of samples, to specimens from 23 localities of the Western Cape Province. Our preliminary results suggest that a total of 6 cryptic species are currently grouped under the name P. callosus. Diagnostic morphological features used to distinguish between species were found on the ventrites and genitalia of the males. Females cannot yet be distinguished reliably based on morphology. Uncorrected interspecific genetic distances based on COI sequences ranged from 3 to 11 %. Among the species of this complex, two were found in orchards and are causing damage. The other species were found in the surrounding, natural environment and seemed to be primarily associated with Asteraceae. More research is needed to explore the niche partitioning of each species, such as geographic distribution, hosts plant associations and phenology. More generally, this research highlights the importance of detailed integrative studies to identify functional taxonomic units of insect pests in agriculture

Parameter Synthesis for Parametric Interval Markov Chains

AELOS_HCERES2020, STR_HCERES2020Interval Markov Chains (IMCs) are the base of a classic probabilistic specification theory introduced by Larsen and Jonsson in 1991. They are also a popular abstraction for probabilistic systems. In this paper we study parameter synthesis for a parametric extension of Interval Markov Chains in which the endpoints of intervals may be replaced with parameters. In particular, we propose constructions for the synthesis of all parameter values ensuring several properties such as consistency and consistent reachability in both the existential and universal settings with respect to implementations. We also discuss how our constructions can be modified in order to synthesise all parameter values ensuring other typical properties

Cavity QED with hybrid nanocircuits: from atomic-like physics to condensed matter phenomena

Circuit QED techniques have been instrumental to manipulate and probe with exquisite sensitivity the quantum state of superconducting quantum bits coupled to microwave cavities. Recently, it has become possible to fabricate new devices where the superconducting quantum bits are replaced by hybrid mesoscopic circuits combining nanoconductors and metallic reservoirs. This mesoscopic QED provides a new experimental playground to study the light-matter interaction in electronic circuits. Here, we present the experimental state of the art of Mesoscopic QED and its theoretical description. A first class of experiments focuses on the artificial atom limit, where some quasiparticles are trapped in nanocircuit bound states. In this limit, the Circuit QED techniques can be used to manipulate and probe electronic degrees of freedom such as confined charges, spins, or Andreev pairs. A second class of experiments consists in using cavity photons to reveal the dynamics of electron tunneling between a nanoconductor and fermionic reservoirs. For instance, the Kondo effect, the charge relaxation caused by grounded metallic contacts, and the photo-emission caused by voltage-biased reservoirs have been studied. The tunnel coupling between nanoconductors and fermionic reservoirs also enable one to obtain split Cooper pairs, or Majorana bound states. Cavity photons represent a qualitatively new tool to study these exotic condensed matter states.Comment: 34 pages, 18 figures, 1 table, minor differences with the published version to appear in Journal of Physics: Condensed Matter as a topical revie

Categorizing chlordecone potential degradation products to explore their environmental fate

EA BIOmE SUPDAT INRAInternational audienceChlordecone (C10Cl10O; CAS number 143-50-0) has been used extensively as an organochlorine insecticide but is nowadays banned and listed on annex A in The Stockholm Convention on Persistent Organic Pollutants (POPs). Although experimental evidences of biodegradation of this compound are scarce, several dechlorination products have been proposed by Dolfing et al. (2012) using Gibbs free energy calculations to explore different potential transformation routes. We here present the results of an in silico classification (TyPol - Typology of Pollutants) of chlordecone transformation products (TPs) based on statistical analyses combining several environmental endpoints and structural molecular descriptors. Starting from the list of putative chlordecone TPs and considering available data on degradation routes of other organochlorine compounds, we used different clustering strategies to explore the potential environmental behaviour of putative chlordecone TPs from the knowledge on their molecular descriptors. The method offers the possibility to focus on TPs present in different classes and to infer their environmental fate. Thus, we have deduced some hypothetical trends for the environmental behaviour of TPs of chlordecone assuming that TPs, which were clustered away from chlordecone, would have different environmental fate and ecotoxicological impact compared to chlordecone. Our findings suggest that mono- and di-hydrochlordecone, which are TPs of chlordecone often found in contaminated soils, may have similar environmental behaviour in terms of persistence

Disentangling the origins of cultivated sweet potato (Ipomoea batatas (L.) Lam.)

Sweet potato (Ipomoea batatas (L.) Lam., Convolvulaceae) counts among the most widely cultivated staple crops worldwide, yet the origins of its domestication remain unclear. This hexaploid species could have had either an autopolyploid origin, from the diploid I. trifida, or an allopolyploid origin, involving genomes of I. trifida and I. triloba. We generated molecular genetic data for a broad sample of cultivated sweet potatoes and its diploid and polyploid wild relatives, for noncoding chloroplast and nuclear ITS sequences, and nuclear SSRs. Our data did not support an allopolyploid origin for I. batatas, nor any contribution of I. triloba in the genome of domesticated sweet potato. I. trifida and I. batatas are closely related although they do not share haplotypes. Our data support an autopolyploid origin of sweet potato from the ancestor it shares with I. trifida, which might be similar to currently observed tetraploid wild Ipomoea accessions. Two I. batatas chloroplast lineages were identified. They show more divergence with each other than either does with I. trifida. We thus propose that cultivated I. batatas have multiple origins, and evolved from at least two distinct autopolyploidization events in polymorphic wild populations of a single progenitor species. Secondary contact between sweet potatoes domesticated in Central America and in South America, from differentiated wild I. batatas populations, would have led to the introgression of chloroplast haplotypes of each lineage into nuclear backgrounds of the other, and to a reduced divergence between nuclear gene pools as compared with chloroplast haplotypes. (Résumé d'auteur

Les genres Entandrophragma (Meliceae) et Dacryodes (Burseraceae) en Afrique centrale atlantique

Dans le genre Entandrophragma, l'étude a été centrée sur les cinq taxons rencontrés en forêt dense humide de terre ferme et de basse altitude (E. angolense et congoense, E. candollei, E. cylindricum, E. utile). Les autres espèces du genre sont situées dans des milieux forestiers (deux d'entre elles) et, souvent, dans le domaine des savanes et forêts claires. Les premières analyses génétiques montrent que ces taxons de forêts denses humides sont proches, plus particulièrement E. cylindricum et E. utile. Deux taxons, placés en synonymie par certains botanistes, E. angolense et E. congoense, n'ont pas pu être différenciés à ce stade. Concernant le genre Dacryodes, les premières analyses phylogénétiques des espèces africaines indiquent qu'elles sont également proches génétiquement ; toutes sont des espèces de forêts denses humides, y compris celles de la région congolaise. Ainsi, les mitotypes dominants (NAD712) pour D. buettneri, D. edulis, D. klaineana, D. igaganga, D. macrophylla et D. normandii sont identiques. Un deuxième mitotype est commun à D. buettneri et à D. edulis. Les autres mitotypes sont rares. L'ADN chloroplastique (rpl16) montre une plus grande variation mais les données sont moins nombreuses. On remarque une très forte différenciation entre deux chlorotypes rencontrés chez D. edulis, même au sein d'une même population cultivée. Des analyses génétiques supplémentaires sont encore nécessaires afin d'évaluer plus précisément les relations et les distances génétiques entre les espèces telles que définies par les botanistes. (Texte intégral

Mutant <i>CTNNB1</i> and histological heterogeneity define metabolic subtypes of hepatoblastoma.

Hepatoblastoma is the most common malignant pediatric liver cancer. Histological evaluation of tumor biopsies is used to distinguish among the different subtypes of hepatoblastoma, with fetal and embryonal representing the two main epithelial components. With frequent &lt;i&gt;CTNNB1&lt;/i&gt; mutations, hepatoblastoma is a Wnt/β-catenin-driven malignancy. Considering that Wnt activation has been associated with tumor metabolic reprogramming, we characterized the metabolic profile of cells from hepatoblastoma and compared it to cells from hepatocellular carcinoma. First, we demonstrated that glucose transporter &lt;i&gt;GLUT3&lt;/i&gt; is a direct TCF4/β-catenin target gene. RNA sequencing enabled to identify molecular and metabolic features specific to hepatoblastoma and revealed that several glycolytic enzymes are overexpressed in embryonal-like compared to fetal-like tumor cells. This led us to implement successfully three biomarkers to distinguish embryonal from fetal components by immunohistochemistry from a large panel of human hepatoblastoma samples. Functional analyses demonstrated that embryonal-like hepatoblastoma cells are highly glycolytic and sensitive to hexokinase-1 silencing. Altogether, our findings reveal a new, metabolic classification of human hepatoblastoma, with potential future implications for patients' diagnosis and treatment

Physico-chemical and biological characterization of an aquifer polluted with ETBE

International audiencePetroleum compounds and among them, gasoline, is the most massively used chemicals worldwide and, as a consequence gasoline derives compounds are the most frequently found contaminants in groundwate