Introgression and persistence of cultivar alleles in wild carrot (Daucus carota) populations in the United States.

PREMISE: Cultivated species and their wild relatives often hybridize in the wild, and the hybrids can survive and reproduce in some environments. However, it is unclear whether cultivar alleles are permanently incorporated into the wild genomes or whether they are purged by natural selection. This question is key to accurately assessing the risk of escape and spread of cultivar genes into wild populations. METHODS: We used genomic data and population genomic methods to study hybridization and introgression between cultivated and wild carrot (Daucus carota) in the United States. We used single nucleotide polymorphisms (SNPs) obtained via genotyping by sequencing for 450 wild individuals from 29 wild georeferenced populations in seven states and 144 cultivars from the United States, Europe, and Asia. RESULTS: Cultivated and wild carrot formed two genetically differentiated groups, and evidence of crop-wild admixture was detected in several but not all wild carrot populations in the United States. Two regions were identified where cultivar alleles were present in wild carrots: California and Nantucket Island (Massachusetts). Surprisingly, there was no evidence of introgression in some populations with a long-known history of sympatry with the crop, suggesting that post-hybridization barriers might prevent introgression in some areas. CONCLUSIONS: Our results provide support for the introgression and long-term persistence of cultivar alleles in wild carrots populations. We thus anticipate that the release of genetically engineered (GE) cultivars would lead to the introduction and spread of GE alleles in wild carrot populations.

All-in-one diagnostic and therapeutic precision thoracic surgery using a hybrid operating theatre: the triple-marking technique.

BACKGROUND: The minimally invasive management of sub-centimetric and often sub-solid lung lesions is quite challenging for thoracic surgeons. As a matter of fact, thoracoscopic wedge resection can often require conversion to thoracotomy when pulmonary lesions cannot be visually identified. Hybrid operating rooms (ORs) can serve as a helpful tool in a multidisciplinary setting, providing real-time lesion imaging and targeting, allowing preoperative or intraoperative percutaneous placement of different lesions targeting techniques to help locate non-palpable lung nodules during video-assisted thoracic surgery. The aim of the study is to assess whether the lung nodule marking using methylene blue, indocyanine green, and gold seeds - the "triple-marking technique" - in the hybrid OR is effective in helping locate non-visible or palpable nodules. METHODS: We conducted a retrospective study on 19 patients with non-palpable lung lesions requiring VATS wedge resection and underwent lesional targeting in the hybrid operating room with different marking systems, including gold seeds placement, methylene blue, or indocyanine green. Lesions were considered non-palpable due to sizing, radiological subsolid aspect, or location and then identified using intraoperative CT scans, also allowing to elaborate needle trajectory. The intraoperative diagnosis was obtained in all of the patients guiding the type of surgery performed. RESULTS: The radio-opaque gold seed marker was used in all of the patients except for two cases that developed intraprocedural pneumothoraces with no major consequences. In these patients, the nodule marking using dyes was still performed and successful in allowing to locate the lesion. Methylene blue and indocyanine green were always used in combination during the dye-targeting phase. Methylene blue appeared to be non-visible in two patients. The indocyanine green was correctly visualized in every patient. We observed the gold seed dislocation in two patients. We were able to identify the lung lesion in all the patients correctly. No conversion was needed. No allergic reactions were observed due to dye administration, and no prophylaxis was performed prior to lesional marking. The lung lesions were visually identified in 100% of the patients thanks to at least one marking technique. CONCLUSIONS: Our experience confirms that the hybrid operating room can represent a suitable tool in helping locate hard-to-find lung lesions in planned VATS resections. Using different techniques, a multiple marking approach seems advisable to maximize the lung lesions detecting rate by direct vision, therefore reducing the VATS conversion rate.

Too early for the ferry: The biogeographic history of the Assamiidae of southeast Asia (Chelicerata: Opiliones, Laniatores).

Opiliones (harvestmen) have come to be regarded as an abundant source of model groups for study of historical biogeography, due to their ancient age, poor dispersal capability, and high fidelity to biogeographic terranes. One of the least understood harvestman groups is the Paleotropical Assamiidae, one of the more diverse families of Opiliones. Due to a labyrinthine taxonomy, poorly established generic and subfamilial boundaries, and the lack of taxonomic keys for the group, few efforts have been undertaken to decipher relationships within this arachnid lineage. Neither the monophyly of the family, nor its exact placement in the harvestman phylogeny, have been established. Here, we assessed the internal phylogeny of Assamiidae using a ten-locus Sanger dataset, sampling key lineages putatively ascribed to this family for five of the ten markers. Our analyses recovered Assamiidae as a monophyletic group, in a clade with the primarily Afrotropical Pyramidopidae and the southeast Asian Beloniscidae. Internal relationships of assamiids disfavored the systematic validity of subfamilies, with biogeography reflecting much better phylogenetic structure than the existing higher-level taxonomy. To assess whether the Asian assamiids came to occupy Indo-Pacific terranes via rafting on the Indian subcontinent, we performed divergence dating to infer the age of the family. Our results show that Indo-Pacific clades are ancient, originating well before the Cretaceous and therefore predate a vicariant mechanism commonly encountered for Paleotropical taxa.

Draft Genome Sequence of "Candidatus Nardonella dryophthoridicola" Strain NARMHE1, Endosymbiont of Metamasius hemipterus (Coleoptera, Curculionidae, Dryophthorinae).

Here, we report the draft genome and annotation of "Candidatus Nardonella dryophthoridicola" strain NARMHE1, obtained via Oxford Nanopore sequencing of the ovaries of its host, the weevil Metamasius hemipterus, from a population from southeast Brazil.

Phylogenetic assessment of the Metamasius hemipterus species complex (Coleoptera, Curculionidae, Dryophthorinae).

Metamasius is a large genus of dryophthorine weevils, with nearly 85 species. Among the economically important pests in the genus, M. hemipterus is currently separated in three subspecies, based largely on color patterns of the elytra, pronotum, and sternum. The tenuous limits of M. hemipterus subspecies were created over fifty years ago and never tested under a phylogenetic framework. Here, for the first time, we address the M. hemipterus species boundaries applying a molecular approach. We constructed a reduced genome representation of a few species using restriction site-associated DNA sequencing (RADseq). Phylogenetic analysis using either a complete supermatrix or only SNPs revealed a clear separation of Metamasius species. We suggest that M. h. carbonarius syn. nov. and M. h. sericeus be treated as the same species, M. sericeus (Oliver) stat. n., and elevate M. h. hemipterus as a separate species M. hemipterus (Linnaeus). We updated Vaurie's identification key to reflect the new species status. This systematic reassessment reflects a more natural classification for these remarkable and economically significant weevils.

Cauchy relation in relaxing liquids.

The Cauchy-like relation M(infinity) = A + BG(infinity) has recently been found to hold for the high frequency limit values of the longitudinal modulus M(infinity) and transverse modulus G(infinity) of viscoelastic liquids, with B approximately 3 in all the investigated systems. The Brillouin scattering results here reported for curing epoxy systems and thermal glass formers give evidence for the validity of a Cauchy-like relation M(') = A + BG(') for the real part of the elastic moduli measured at finite frequencies. Our results suggest as well the validity of a pure Cauchy relation DeltaM = 3 DeltaG for the relaxation strengths of longitudinal and shear moduli in relaxing liquids.