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Ribes L. belongs to the Grossulariaceae family and has important edible, medicinal, ornamental, and landscaping values. Taxonomic classification within this genus is difficult due to its large variety of species, wide distribution, large morphological variations, and presence of two complex taxonomic groups with bisexual or unisexual flowers. Our study aims to clarify the phylogenetic relationships of Ribes L. taxa in China, and further, to provide a reference for a revised global classification of it. The phylogenetic analysis of 52 Ribes L. samples from 30 species was constructed based on restriction site-associated DNA sequencing and single nucleotide polymorphisms. Afterward, two important taxonomic characters were selected for ancestral state reconstruction over the molecular phylogeny. The results showed that the 52 samples could be divided into six branches, i.e., six subgenera, which caused some controversy regarding the morphological classification of Ribes L. in China. The molecular phylogeny supported the separation of subg. Coreosma from subg. Ribesia and subg. Hemibotrya from subg. Berisia and validated the rationale for recognizing subg. Grossularia as an independent subgenus, the rationality of which was further verified by the reconstruction of ancestor traits. Gene flow among Ribes L. was identified and further confirmed our results.

The microstructure and electromagnetic properties of melt-spun Nd–Fe–B nanocomposites, which have been dealt with by the ball milling process with different milling times, are studied specifically in this paper. The powder size ranges from 20 μm to 5 μm after different milling times. Moreover the powder particles even remain flake-like shape after 11 h milling time. X-ray diffraction spectra strongly suggest that all samples only have the single α-Fe phase. By using the complex permeability ( μ = μ ′ − μ ″) and permittivity ( e = e ′ − e ″) within 2 to 18 GHz frequency range, determined by vector network analysis, the experiment shows that the permeability of flake-like Nd 3 Fe 68 Co 18 B 11 can be increased while its permittivity is decreased by increasing the milling time. For the sample with 11 h milling time, its imaginary permeability μ ″ can be increased to an abnormal state below the frequency of 6 GHz. Based on transmission line theory, it is calculated that the Nd 3 Fe 68 Co 18 B 11 composites can achieve their optimal reflection loss (RL = − 8 dB) at 3.7 GHz with a matching thickness of 1.5 mm. This paper shows the possibility to obtain good microwave absorbing properties at a proper milling time for melt spun Nd–Fe–B nanocomposites.

The effects of silane coupling agent doping on the microstructure and microwave properties of melt-spun Nd-Fe-Co alloys were investigated. All as-milled powders, with or without silane coupling agent treatment, were characterized as flake-like shape. However, it is found that with the addition of 0.25 mL coupling agent, the as-milled Nd-Fe-Co powders can deagglomerate and become more uniform dispersion with smaller thickness. In contrast, the excessive addition of coupling agent led to somewhat higher thickness of the flakes and much more amount of coupling agent on the surface of powder. The electromagnetic properties show that the Reflection loss will arrive −27.1 dB at 4.2 GHz, for the addition of 0.25 mL coupling agent powders. The probably reasons for this are discussed on the basis of the morphology of the powders, uniform dispersion and the physical coating between the polymer and coupling agent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Using x-ray precession method, it is found that the distribution of reciprocal lattice of β-W structure is just the distortion of the reciprocal space of Al6Li3Cu quasicrystal structure. Except the distortion, the x-ray diffraction patterns along 5-fold, 3-fold and 2-fold axes can be observed. Their angular relations satisfy well with those of the perfect icosahedral symmetry; and all the diffraction spots can be indexed approxmately to be six-dimension and strictly in three-dimension.

Antibody 10E8 targets the membrane-proximal external region (MPER) of HIV-1 gp41, neutralizes >97% of HIV-1 isolates, and lacks the auto-reactivity often associated with MPER-directed antibodies. The developmental pathway of 10E8 might therefore serve as a promising template for vaccine design, but samples from time-of-infection—often used to infer the B cell record—are unavailable. In this study, we used crystallography, next-generation sequencing (NGS), and functional assessments to infer the 10E8 developmental pathway from a single time point. Mutational analysis indicated somatic hypermutation of the 2nd-heavy chain-complementarity determining region (CDR H2) to be critical for neutralization, and structures of 10E8 variants with V-gene regions reverted to genomic origin for heavy-and-light chains or heavy chain-only showed structural differences >2 Å relative to mature 10E8 in the CDR H2 and H3. To understand these developmental changes, we used bioinformatic sieving, maximum likelihood, and parsimony analyses of immunoglobulin transcripts to identify 10E8-lineage members, to infer the 10E8-unmutated common ancestor (UCA), and to calculate 10E8-developmental intermediates. We were assisted in this analysis by the preservation of a critical D-gene segment, which was unmutated in most 10E8-lineage sequences. UCA and early intermediates weakly bound a 26-residue-MPER peptide, whereas HIV-1 neutralization and epitope recognition in liposomes were only observed with late intermediates. Antibody 10E8 thus develops from a UCA with weak MPER affinity and substantial differences in CDR H2 and H3 from the mature 10E8; only after extensive somatic hypermutation do 10E8-lineage members gain recognition in the context of membrane and HIV-1 neutralization.