Three new species of Eupetersia Blüthgen, 1928 (Hymenoptera, Halictidae) from the Oriental Region

Three new species, Eupetersia (Nesoeupetersia) singaporensis sp. nov., collected in a mangrove swamp in Singapore, and Eupetersia (Nesoeupetersia) sabahensis sp. nov., collected in the mountains of Sabah, Borneo, and Eupetersia (Nesoeupetersia) yanegai sp. nov., collected in Thailand, are described. This genus is more diversified in the sub-Saharan region, including Madagascar. The only other Oriental species, E. nathani (Baker, 1974), was described from India and is diagnosed and re-illustrated here

Capalictus, a new subgenus of Lasioglossum Curtis, 1833 from South Africa, with description of three new species (Hymenoptera, Apoidea, Halictidae)

Capalictus, a new subgenus of Lasioglossum Curtis, 1833 (Hymenoptera, Apoidea, Halictidae), endemic to the South African Cape Province, is described. The type species is Halictus mosselinus Cockerell, 1945. Evylaeus (Sellalictus) fynbosensis (Pauly et al., 2008) is a new junior synonym of L. (C.) mosselinum. Three new species are described: Lasioglossum (Capalictus) hantamense sp. nov., L. (C.) tigrinum sp. nov. and L. (C.) timmermanni sp. nov. DNA sequence data from three nuclear genes support morphologically-determined species limits. Capalictus is a basal clade of the Hemihalictus series of Lasioglossum

Analyse du contexte de formation d’un jeune athlète. Etude de cas

peer reviewedNous nous sommes intéressés à un jeune espoir sportif belge pour lequel nous avons tenté de modéliser la structure d’encadrement. Pour ce faire, nous avons opté pour des entretiens exploratoires semi‐directifs dans les milieux familial, sportif et scolaire de l’athlète. L’analyse des informations recueillies nous a permis de dévoiler la qualité de la structure actuellement mise en place et, notamment, le rôle déterminant du père qui se charge de coordonner et de contrôler l’ensemble de celle‐ci. Notre étude a également conscientisé les acteurs sur le fonctionnement de la structure et s’est montrée efficace pour améliorer les relations entre les principaux acteurs

Numerical Simulations to Evaluate and Compare the Performances of Existing and Novel Degrader Materials for Proton Therapy

The performance of the energy degrader in terms of beam properties directly impacts the design and cost of cyclotron-based proton therapy centers. The aim of this study is to evaluate the performances of different existing and novel degrader materials. The quantitative estimate is based on detailed GEANT4 simulations that analyze the beam-matter interaction and provide a determination of the beam emittance increase and transmission. Comparisons between existing (aluminum, graphite, beryllium) and novel (boron carbide and diamond) degrader materials are provided and evaluated against semi-analytical models of multiple Coulomb scattering. The results showing a potential in emittance reduction for novel materials are presented and discussed in detail.Comment: Submitted for IPAC 2018 "light peer review

Improvement in real time detection and selectivity of phthalocyanine gas sensors dedicated to oxidizing pollutants evaluation

International audienceA sensor microsystem prototype, using copper phthalocyanine thin film as sensitive layer, and dedicated to ozone evaluation, was developed. The methodology implemented is based on cyclic sensor recalibrations by thermal cleaning of the sensitive membrane, and on pollutant concentration quantification according to the kinetics of sensor response. Results of laboratory experiments for various NO2 and O3 concentrations, in the range of 10–200 ppb, illustrate the selectivity of CuPc sensors towards ozone, obtained by our methodology. We have shown that ozone selectivity is especially improved for short time of exposure (few minutes) and for phthalocyanine layer maintained at low temperature (80 °C). For optimal conditions, our microsystem exhibits a threshold lower than 10 ppb, a resolution lower than 10 ppb, and good reproducibility of measurements. Performances obtained in real urban atmosphere are satisfying to ensure real time evaluation of ozone during several days. Long-term stability and the detection of NO2 by associating chemical filters to our microsystem will be also discussed

Traditional rangeland management can conserve insect pollinators in a semi-arid rangeland, northern Tanzania

This research article was published Elsevier, 2021Globally, pollinators are threatened by land-use changes, including habitat degradation. East African rangelands are under pressure due to livestock population increase and overutilization, which lead to degradation of vegetation and soils. While traditional grazing management is widely used to restore vegetation, little is known how this affects insect pollinators. We investigated whether differently managed rangeland areas harbor different insect pollinator abundance, richness and diversity in Simanjiro, Tanzania. We established twelve blocks in four grazing areas under different management categories (private and communal enclosures, wet and dry season grazing lands) and used pan traps and sweep nets to collect insect pollinators. We collected a total of 1977 insects, representing 44 families and 239 species. Beetles were most frequently trapped, with 646 (33%) individuals, followed by 522 bees (26%). Pollinator abundance was twice as high in the private enclosure compared to the communal dry grazing area (χ2 = 27.63, P < 0.001). We found a strong positive correlation between floral and pollinator abundances (r = 0.68, P = 0.015) but not for pollinator species richness and diversity. Bee species abundance and diversity were also significantly higher (χ2 = 68.00, P < 0.0001) in enclosures compared to open rangelands and were significantly influenced by season (χ2 = 220.73, P < 0.0001). Apis mellifera (honey bee) and Lasioglossum of the subgenus Ipomalictus were the most abundant bee species with 107 (21%) and 105 (20%) individuals, respectively. We noticed a significant interaction between season and management on influencing bee pollinator numbers (χ2 = 19.84, P = 0.0002). We conclude that traditional rangeland management can strongly influence pollinator abundance and communities. Our study will aid in developing rangeland management strategies to promote conservation of and enhance pollinator availability in tropical rangelands

Using next-generation sequencing to improve DNA barcoding: lessons from a small-scale study of wild bee species (Hymenoptera, Halictidae)

International audienceAbstractThe parallel sequencing of targeted amplicons is a scalable application of next-generation sequencing (NGS) that can advantageously replace Sanger sequencing in certain DNA barcoding studies. It can be used to sequence different PCR products simultaneously, including co-amplified products. Here, we explore this approach by simultaneously sequencing five markers (including the DNA barcode and a diagnostic marker of Wolbachia) in 12 species of Halictidae that were previously DNA barcoded using Sanger sequencing. Consensus sequences were obtained from fresh bees with success rates of 74–100% depending on the DNA fragment. They improved the phylogeny of the group, detected Wolbachia infections (in 8/21 specimens) and characterised haplotype variants. Sequencing cost per marker and per specimen (11.43 €) was estimated to decrease (< 5.00 €) in studies aiming for a higher throughput. We provide guidelines for selecting NGS or Sanger sequencing depending on the goals of future studies

Integrative taxonomy resuscitates two species in the Lasioglossum villosulum complex (Kirby, 1802) (Hymenoptera: Apoidea: Halictidae)

peer reviewedMorphological and allozyme analyses suggested the occurrence of a pseudocryptic species in the Lasioglossum villosulum (Kirby, 1802) species complex (Hymenoptera: Halictidae). We analysed the morphology of more than 1500 specimens and the DNA barcode fragment of the cytochrome c oxidase subunit I (COI) of 102 specimens of this species complex from several Palaearctic countries. Our phylogenetic tree reconstructions, based on maximum likelihood and Bayesian inference revealed one clade corresponding to all specimens morphologically identified as Lasioglossum medinai (Vachal, 1895) and one divergent specimen morphologically identified as Lasioglossum berberum (Benoist, 1941). The other specimens, morphologically identified as L. villosulum, aggregated into at least three other lineages in our phylogenetic trees. The tree-based species delineations methods based on the Generalized Mixed Yule Coalescent (GMYC) model and the Bayesian Poisson Tree Process (bPTP) identified five to ten candidate species within the L. villosulum species complex, with L. medinai and L. berberum consistently recognized as separated from all other candidate species. Diagnostic morphological differences were found among L. medinai, L. berberum and the remaining specimens identified as L. villosulum. No diagnostic morphological differences were found to distinguish the different phylogenetic candidate species or lineages found within L. villosulum and L. medinai. Thus,both genetic and morphological approaches support the existence of L. medinai and L. berberum as distinct species from L. villosulum

Lasioglossum dorchini (Hymenoptera: Apoidea: Halictidae) a new species of bee from Israel

This paper describes a new species, Lasioglossum dorchini, occuring in sand dunes in Israel. It is close to Lasioglossum leptocephalum. Its phylogenetic relationships with the other species of the virens/littorale group are analyzed