6 research outputs found

    Unsupervised classification to improve the quality of a bird song recording dataset

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    Open audio databases such as Xeno-Canto are widely used to build datasets to explore bird song repertoire or to train models for automatic bird sound classification by deep learning algorithms. However, such databases suffer from the fact that bird sounds are weakly labelled: a species name is attributed to each audio recording without timestamps that provide the temporal localization of the bird song of interest. Manual annotations can solve this issue, but they are time consuming, expert-dependent, and cannot run on large datasets. Another solution consists in using a labelling function that automatically segments audio recordings before assigning a label to each segmented audio sample. Although labelling functions were introduced to expedite strong label assignment, their classification performance remains mostly unknown. To address this issue and reduce label noise (wrong label assignment) in large bird song datasets, we introduce a data-centric novel labelling function composed of three successive steps: 1) time-frequency sound unit segmentation, 2) feature computation for each sound unit, and 3) classification of each sound unit as bird song or noise with either an unsupervised DBSCAN algorithm or the supervised BirdNET neural network. The labelling function was optimized, validated, and tested on the songs of 44 West-Palearctic common bird species. We first showed that the segmentation of bird songs alone aggregated from 10% to 83% of label noise depending on the species. We also demonstrated that our labelling function was able to significantly reduce the initial label noise present in the dataset by up to a factor of three. Finally, we discuss different opportunities to design suitable labelling functions to build high-quality animal vocalizations with minimum expert annotation effort

    Elevational gradient of Hemiptera (Heteroptera, Auchenorrhyncha) on a tropical mountain in Papua New Guinea

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    International audienceMalaise trap sampling ofHemiptera (Heteroptera; Auchenorrhyncha) was conducted at 500 m intervals along an elevational gradient from 200 m to 3,700 m on the east slope of MountWilhelm, Madang Province, Papua New Guinea. Hemiptera had a decrease in morphospecies richness and overall abundance with increasing elevation, however, the Heteroptera did not exhibit either pattern. A few species were relatively abundant at each elevation, whereas the majority of species were represented by ≤5 specimens. Morphospecies richness of Auchenorrhyncha, Cicadomorpha, Fulgoromorpha, Cicadellidae, Cixiidae, and Derbidae also decreased with increasing elevation but abundance decline was not significant due to the large number of specimens captured at 200 m relative to those captured at higher elevations. The percentage of Cicadomorpha specimens decreased with increasing elevation relative to that of the Fulgoromorpha which increased with increasing elevation. Environmental factors that may influence patterns of species richness along the elevational gradient are discussed

    Cercopidae spittle-bugs (Hemiptera, Cicadomorpha) of Madagascar: a new species of Bourgoinrana and revision of the Locris species

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    The Locris species and subspecies from Madagascar are revised and a new combination is proposed: Locris johannae var. nigrolimbata Lallemand, 1910 to L. nigrolimbata comb. nov. Illustrations and description of male terminalia are given for the first time for the three Locris species and an identification key is provided. A new species of the Malagasy endemic genus Bourgoinrana Soulier-Perkins, 2012 is described: B. beondrokaensis Le Cesne & Soulier-Perkins sp. nov. An updated identification key to the species of Bourgoinrana is provided

     Coframalaxius bletteryi gen. et sp. nov. from subterranean habitat in Southern France (Hemiptera, Fulgoromorpha, Cixiidae, Oecleini)

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    A new planthoppers genus and species of Cixiidae Oecleini, Coframalaxius bletteryi gen. et sp. nov. newly discovered in a cave near Nice in southern France, is described. Molecular analysis confirms the morphology-based classification of Coframalaxius as sister to Trigonocranus within the Oecleni. Several morphological characters are further discussed. A double-grasping coxo-femoral and femoro-tibial system is regarded as apomorphic for the oecline taxa and would allow the nymph to firmly grab the roots and rootlets on which it feeds or use to progress in the soil. Wing vein patterns are discussed in the Cixiidae: 1) for the forewings, Oecleini belong to the trifid type of the anterior MP branch, leading to the reinterpretation of some recently described Neotropical species, 2) for the hindwing, four connection types (U-, V-, Y- and I-types) between MP and CuA are described. Oecleini belongs to I-type with a complete fusion of MP3+4 with CuA1. Although the area where the cave is located is well-studied with respect to its regularly sampled epigean fauna for many years, the taxon is new to science, highlighting its probable completely hypogean life cycle and leading to consider Coframalaxius bletteryi as an eutroglophile species

    Nationwide incidence of sarcomas and connective tissue tumors of intermediate malignancy over four years using an expert pathology review network

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    International audienceBackground Since 2010, nationwide networks of reference centers for sarcomas (RREPS/NETSARC/RESOS) collected and prospectively reviewed all cases of sarcomas and connective tumors of intermediate malignancy (TIM) in France. Methods The nationwide incidence of sarcoma or TIM (2013–2016) was measured using the 2013 WHO classification and confirmed by a second independent review by expert pathologists. Simple clinical characteristics, yearly variations and correlation of incidence with published clinical trials are presented and analyzed. Results Over 150 different histological subtypes are reported from the 25172 patients with sarcomas (n = 18712, 74,3%) or TIM (n = 6460, 25.7%), with n = 5838, n = 6153, n = 6654, and n = 6527 yearly cases from 2013 to 2016. Over these 4 years, the yearly incidence of sarcomas and TIM was therefore 70.7 and 24.4 respectively, with a combined incidence of 95.1/10 6 /year, higher than previously reported. GIST, liposarcoma, leiomyosarcomas, undifferentiated sarcomas represented 13%, 13%, 11% and 11% of tumors. Only GIST, as a single entity had a yearly incidence above 10/10 6 /year. There were respectively 30, 64 and 66 different histological subtypes of sarcomas or TIM with an incidence ranging from 10 to 1/10 6 , 1–0.1/10 6 , or < 0.1/10 6 /year respectively. The 2 latter incidence groups represented 21% of the patients with 130 histotypes. Published phase III and phase II clinical trials (p<10 −6 ) are significantly higher with sarcomas subtypes with an incidence above 1/10 6 per. Conclusions This nationwide registry of sarcoma patients, with exhaustive histology review by sarcoma experts, shows that the incidence of sarcoma and TIM is higher than reported, and that tumors with a very low incidence (1<10 6 /year) are less likely to be included in clinical trials
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