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  1. Abstract

    Leafhoppers comprise over 20,000 plant‐sap feeding species, many of which are important agricultural pests. Most species rely on two ancestral bacterial symbionts,SulciaandNasuia, for essential nutrition lacking in their phloem and xylem plant sap diets. To understand how pest leafhopper genomes evolve and are shaped by microbial symbioses, we completed a chromosomal‐level assembly of the aster leafhopper's genome (ALF;Macrosteles quadrilineatus). We compared ALF's genome to three other pest leafhoppers,Nephotettix cincticeps,Homalodisca vitripennis, andEmpoasca onukii, which have distinct ecologies and symbiotic relationships. Despite diverging ~155 million years ago, leafhoppers have high levels of chromosomal synteny and gene family conservation. Conserved genes include those involved in plant chemical detoxification, resistance to various insecticides, and defence against environmental stress. Positive selection acting upon these genes further points to ongoing adaptive evolution in response to agricultural environments. In relation to leafhoppers' general dependence on symbionts, species that retain the ancestral symbiont,Sulcia, displayed gene enrichment of metabolic processes in their genomes. Leafhoppers with bothSulciaand its ancient partner,Nasuia, showed genomic enrichment in genes related to microbial population regulation and immune responses. Finally, horizontally transferred genes (HTGs) associated with symbiont support ofSulciaandNasuiaare only observed in leafhoppers that maintain symbionts. In contrast, HTGs involved in non‐symbiotic functions are conserved across all species. The high‐quality ALF genome provides deep insights into how host ecology and symbioses shape genome evolution and a wealth of genetic resources for pest control targets.

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    Free, publicly-accessible full text available April 1, 2025
  2. Free, publicly-accessible full text available March 1, 2025
  3. Room-temperature sodium-sulfur (RT Na-S) batteries have attracted ever-increasing attention because of their enhanced energy density and low price. Although the performance of RT Na-S batteries is obtained in many other research, the basic mechanism and kinetics have not involved yet, especially in discharge product growth, which affects electrochemical performance. Meanwhile, designed additional redox activities (in the presence of oxygen) could simultaneously suppress sodium polysulfide shuttling and enhance energy density according to our group reported. However, the kinetic study of the intermediate has not been explored. In this work, we discussed the deposition of low-order sodium polysulfide (Na2Sx, x ≤ 2) in different potentials and types of glyme-solvents in Na-S and Na/(O2)-S system. The results show that the morphology of deposition Na2Sx(x ≤ 2) is affected by interfacial energy barrier controlled by overpotentials and the radius of sodium ions, which produced the precipitation of particle shape rather than film. Potentiostatic experiments show the kinetics are elevated in the presence of oxygen. In addition, the exchange current density of different sodium polysulfides was studied. The high-order sodium polysulfide has a lower exchange current density than that of low-order sodium polysulfide in Na-S system, requiring greater driving force, while transformation of the intermediate from high-order oxy-sulfur to low-order oxy-sulfur species require less impulse in Na/(O2)-S systems. This paper provides new understandings of the deposition mechanism and kinetics of Na2Sx(x ≤ 2) Na-S and Na/(O2)-S system in and to choose the appropriate solvent and potential.

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  4. Free, publicly-accessible full text available December 1, 2024
  5. Larracuente, Amanda (Ed.)

    Genomes of aphids (family Aphididae) show several unusual evolutionary patterns. In particular, within the XO sex determination system of aphids, the X chromosome exhibits a lower rate of interchromosomal rearrangements, fewer highly expressed genes, and faster evolution at nonsynonymous sites compared with the autosomes. In contrast, other hemipteran lineages have similar rates of interchromosomal rearrangement for autosomes and X chromosomes. One possible explanation for these differences is the aphid's life cycle of cyclical parthenogenesis, where multiple asexual generations alternate with 1 sexual generation. If true, we should see similar features in the genomes of Phylloxeridae, an outgroup of aphids which also undergoes cyclical parthenogenesis. To investigate this, we generated a chromosome-level assembly for the grape phylloxera, an agriculturally important species of Phylloxeridae, and identified its single X chromosome. We then performed synteny analysis using the phylloxerid genome and 30 high-quality genomes of aphids and other hemipteran species. Unexpectedly, we found that the phylloxera does not share aphids’ patterns of chromosome evolution. By estimating interchromosomal rearrangement rates on an absolute time scale, we found that rates are elevated for aphid autosomes compared with their X chromosomes, but this pattern does not extend to the phylloxera branch. Potentially, the conservation of X chromosome gene content is due to selection on XO males that appear in the sexual generation. We also examined gene duplication patterns across Hemiptera and uncovered horizontal gene transfer events contributing to phylloxera evolution.

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    Free, publicly-accessible full text available December 1, 2024
  6. Free, publicly-accessible full text available May 1, 2024
  7. Abstract

    Despite remarkable progress in the development of halide perovskite materials and devices, their integration into nanoscale optoelectronics has been hindered by a lack of control over nanoscale patterning. Owing to their tendency to degrade rapidly, perovskites suffer from chemical incompatibility with conventional lithographic processes. Here, we present an alternative, bottom-up approach for precise and scalable formation of perovskite nanocrystal arrays with deterministic control over size, number, and position. In our approach, localized growth and positioning is guided using topographical templates of controlled surface wettability through which nanoscale forces are engineered to achieve sub-lithographic resolutions. With this technique, we demonstrate deterministic arrays of CsPbBr3nanocrystals with tunable dimensions down to <50 nm and positional accuracy <50 nm. Versatile, scalable, and compatible with device integration processes, we then use our technique to demonstrate arrays of nanoscale light-emitting diodes, highlighting the new opportunities that this platform offers for perovskites’ integration into on-chip nanodevices.

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