Molecular Phylogeny of the Ant Subfamily Formicinae (Hymenoptera, Formicidae) from China Based on Mitochondrial Genes

To resolve long-standing discrepancies in the relationships among genera within the ant subfamily Formicinae, a phylogenetic study of Chinese Formicine ants based on three mitochondria genes (Cyt b, COI, COII) was conducted. Phylogenetic trees obtained in the current study are consistent with several previously reported trees based on morphology, and specifically confirm and reinforce the classifications made by Bolton (1994). The tribes Lasiini, Formicini, Plagiolepidini and Camponotini are strongly supported, while Oecophyllini has moderate support despite being consistent across all analyses. We have also established that the genus Camponotus and Polyrhachis are indeed not monophyletic. Additionally, we found strong evidence for Polyrhachis paracamponota, as described by Wu and Wang in 1991, to be corrected as Camponotus based on molecular, morphological and behavioral data

Towards diluted magnetism in TaAs

Magnetism in Weyl semimetals is desired to investigate the interaction between the magnetic moments and Weyl fermions, e.g. to explore anomalous quantum Hall phenomena. Here we demonstrate that proton irradiation is an effective tool to induce ferromagnetism in the Weyl semimetal TaAs. The intrinsic magnetism is observed with a transition temperature above room temperature. The magnetic moments from d states are found to be localized around Ta atoms. Further, the first-principles calculations indicate that the d states localized on the nearest-neighbor Ta atoms of As vacancy sites are responsible for the observed magnetic moments and the long-ranged magnetic order. The results show the feasibility of inducing ferromagnetism in Weyl semimetals so that they may facilitate the applications of this material in spintronics.Comment: 20 pages, 6 figure

Flexible Informed Trees (FIT*): Adaptive Batch-Size Approach for Informed Sampling-Based Planner

In modern approaches to path planning and robot motion planning, anytime almost-surely asymptotically optimal planners dominate the benchmark of sample-based planners. A notable example is Batch Informed Trees (BIT*), where planners iteratively determine paths to groups of vertices within the exploration area. However, maintaining a consistent batch size is crucial for initial pathfinding and optimal performance, relying on effective task allocation. This paper introduces Flexible Informed Tree (FIT*), a novel planner integrating an adaptive batch-size method to enhance task scheduling in various environments. FIT* employs a flexible approach in adjusting batch sizes dynamically based on the inherent complexity of the planning domain and the current n-dimensional hyperellipsoid of the system. By constantly optimizing batch sizes, FIT* achieves improved computational efficiency and scalability while maintaining solution quality. This adaptive batch-size method significantly enhances the planner's ability to handle diverse and evolving problem domains. FIT* outperforms existing single-query, sampling-based planners on the tested problems in R^2 to R^8, and was demonstrated in real-world environments with KI-Fabrik/DARKO-Project Europe.Comment: 8 pages,6 figure

Divergence of a genomic island leads to the evolution of melanization in a halophyte root fungus

AbstractUnderstanding how organisms adapt to extreme living conditions is central to evolutionary biology. Dark septate endophytes (DSEs) constitute an important component of the root mycobiome and they are often able to alleviate host abiotic stresses. Here, we investigated the molecular mechanisms underlying the beneficial association between the DSE Laburnicola rhizohalophila and its host, the native halophyte Suaeda salsa, using population genomics. Based on genome-wide Fst (pairwise fixation index) and Vst analyses, which compared the variance in allele frequencies of single-nucleotide polymorphisms (SNPs) and copy number variants (CNVs), respectively, we found a high level of genetic differentiation between two populations. CNV patterns revealed population-specific expansions and contractions. Interestingly, we identified a ~20 kbp genomic island of high divergence with a strong sign of positive selection. This region contains a melanin-biosynthetic polyketide synthase gene cluster linked to six additional genes likely involved in biosynthesis, membrane trafficking, regulation, and localization of melanin. Differences in growth yield and melanin biosynthesis between the two populations grown under 2% NaCl stress suggested that this genomic island contributes to the observed differences in melanin accumulation. Our findings provide a better understanding of the genetic and evolutionary mechanisms underlying the adaptation to saline conditions of the L. rhizohalophila–S. salsa symbiosis.</jats:p

Pezicula neosporulosa sp. nov. (Helotiales, Ascomycota), an endophytic fungus associated with Abies spp. in China and Europe

A new species of Pezicula, P. neosporulosa associated with Abies alba in the Netherlands and A. beshanzuensis in China is described, illustrated and compared to its sister species P. sporulosa, P. cinnamomea and P. eucrita. Morphologically, P. neosporulosa is shown to be similar to P. sporulosa both in sexual and asexual sporulating structures. However, from China the species is only known from endophytic isolates, and sporulating structures were never obtained in them. In contrast to the three sister species, the new species does not produce microconidia directly from ascospores or from macroconidia, but only from conidiophores in conidiomata. Moreover, the colony appearance is highly variable in endophytic isolates. Bayesian, maximum parsimony and maximum-likelihood phylogenetic analyses based on four unlinked loci (internal transcribed spacer, RPB2, TEF-1a and b-tubulin) in concatenated datasets confirmed that all isolates in P. neosporulosa were well separated from closely allied species with high bootstrap value and posterior probability. Taken together, the molecular and morphological evidence supports the introduction of P. neosporulosa as a novel taxon

Optimization of Split Transmitter-Receiver Digital Nonlinearity Compensation in Bi-Directional Raman Unrepeatered System

A theoretical model of the nonlinear signal-to-noise interaction (NSNI) in a bi-directional Raman amplified system with receiver-side digital back-propagation (DBP) or split-DBP is given, which is helpful for the design of such a system. In the proposed model, the distributed Raman gain and the spontaneous Raman scattering are taken into account. The results of the theoretical calculation are compared with the results of transmission simulations, which indicates that the theoretical model matches well with the results of simulations when the pre-compensation length is less than 100 km. For the cases of pre-compensation lengths more than 100 km, the theoretical model has an error of less than 0.1 dB compared with the simulations. By using the theoretical model, the efficiency of the split-DBP is analyzed, and the results are compared with transmission simulations. Both the results of theoretical calculation and simulations show that the split-DBP can effectively mitigate the NSNI in such a system. By adopting split-DBP, with an appropriate pre-compensation length, the signal-to-noise ratio (SNR) of the signal increases by about 1 dB. In addition, the impact of the double Rayleigh scattering (DRB) is also analyzed using the proposed model, and the results show that DRB has little impact on the system

Gel electrophoresis of the amplified partial genes of β-glucosidase, laccase and cellobiohydrolase from <i>Lophodermium</i> isolates.

<p>“M” indicates the size marker.</p