Statistical Representation of Stacking Disorder in Layered Covalent Organic Frameworks

Covalent organic frameworks (COFs) are among the fastest-growing classes of materials with an almost unlimited number of achievable structures, topologies, and functionalities. The exact structure of layered COFs is, however, hard to determine due to an often significant mismatch between experimental powder X-ray diffraction (PXRD) pattern and predicted geometries. We attribute these discrepancies to an inherent disorder in the stacking of layered COFs, invalidating standard theoretical three-dimensional (3D) models. We have represented the structures of COF-1, COF-5, and ZnPc-pz by stacking layers following the Maxwell–Boltzmann energy distribution of their stacking modes. The simulated PXRD patterns of the statistical COF models are close to the experimental ones, featuring an unprecedented agreement in peak intensity, width, and asymmetry. The rarely considered ABC stacking mode proved to be important in layered COFs, as well as including solvent molecules. Our model also shows several general features in PXRD originating from the stacking disorder

Data_Sheet_1_Genome-wide association study in Alzheimer’s disease: a bibliometric and visualization analysis.CSV

BackgroundThousands of research studies concerning genome-wide association studies (GWAS) in Alzheimer’s disease (AD) have been published in the last decades. However, a comprehensive understanding of the current research status and future development trends of GWAS in AD have not been clearly shown. In this study, we tried to gain a systematic overview of GWAS in AD by bibliometric and visualization analysis.MethodsThe literature search terms are: (“genome-wide analysis” or “genome-wide association study” or “whole-genome analysis”) AND (“Alzheimer’s Disease” or “Alzheimer Disease”). Relevant publications were extracted from the Web of Science Core Collection (WoSCC) database. Collected data were further analyzed using VOSviewer, CiteSpace and R package Bibliometrix. The countries, institutions, authors and scholar collaborations were investigated. The co-citation analysis of publications was visualized. In addition, research hotspots and fronts were examined.ResultsA total of 1,350 publications with 59,818 citations were identified. The number of publications and citations presented a significant rising trend since 2013. The United States was the leading country with an overwhelming number of publications (775) and citations (42,237). The University of Washington and Harvard University were the most prolific institutions with 101 publications each. Bennett DA was the most influential researcher with the highest local H-index. Neurobiology of Aging was the journal with the highest number of publications. Aβ, tau, immunity, microglia and DNA methylation were research hotspots. Disease and causal variants were research fronts.ConclusionThe most frequently studied AD pathogenesis and research hotspots are (1) Aβ and tau, (2) immunity and microglia, with TREM2 as a potential immunotherapy target, and (3) DNA methylation. The research fronts are (1) looking for genetic similarities between AD and other neurological diseases and syndromes, and (2) searching for causal variants of AD. These hotspots suggest noteworthy directions for future studies on AD pathogenesis and genetics, in which basic research regarding immunity is promising for clinical conversion. The current under-researched directions are (1) GWAS in AD biomarkers based on large sample sizes, (2) studies of causal variants of AD, and (3) GWAS in AD based on non-European populations, which need to be strengthened in the future.</p

Galectin-9 induced apoptosis of Con A–activated CD4⁺ T cells at day-5.

<p>(A) The purity of isolated CD4⁺ T cells. (B) Spleen CD4⁺ T cells, isolated from untreated mice, were cultured with 10 µg/mL Con A for 5 days and then cultured for 24 hours at 37°C with or without 30 mM lactose followed by indicated doses of galectin-9, then apoptotic cells were assessed by FACS. (C) Time-course of galectin-9 (1 µM) induced apoptosis of day-5 Con A–activated T cells. (D) Absolute number of live cells after galectin-9 treatment, determined by Trypan blue dye exclusion. The results were presented as the mean ± SD of three separate experiments. *, P<0.05 vs PBS treatment.</p

Chemical composition and antibacterial activity of the essential oil from <i>Pyrrosia tonkinensis</i> (Giesenhagen) Ching

<p>The present study aimed to analyse the chemical components of the essential oil from <i>Pyrrosia tonkinensis</i> by GC-MS and evaluate the <i>in vitro</i> antibacterial activity. Twenty-eight compounds, representing 88.1% of the total essential oil, were identified and the major volatile components were <i>trans</i>-2-hexenal (22.1%), followed by nonanal (12.8%), limonene (9.6%), phytol (8.4%), 1-hexanol (3.8%), 2-furancarboxaldehyde (3.5%) and heptanal (3.1%). The antibacterial assays showed that the essential oil of <i>P. tonkinensis</i> had good antibacterial activities against all the tested microorganisms. This paper first reported the chemical composition and antimicrobial activity of the essential oil from <i>P. tonkinensis.</i></p

Galectin-9 induced apoptosis of CD4⁺ T cells <i>in vivo</i>.

<p> Galectin-9 (100 µg per mouse) or PBS was administrated i.v. to Balb/c mice (n = 8 per group) 30 min before Con A injection (20 mg kg^–1). The splenocytes were isolated 24 h later. (A) Fas, FasL and CD25 expression on CD4⁺ T cells are shown. (B) Apoptosis of CD4⁺ T cells was analyzed by FACS. (C) Differentially induced apoptosis of CD4⁺ effector T cells and regulatory T cells by galectin-9 in Con A treated mice. Similar results were obtained in 3 separate experiments and the representative results were shown. Normal, normal mice; PBS, PBS pretreatment in Con A-treated mice; Gal-9, galectin-9 pretreatment in Con A-treated mice.</p

Additional file 2: of Diversity of the Bosmina (Cladocera: Bosminidae) in China, revealed by analysis of two genetic markers (mtDNA 16S and a nuclear ITS)

The obtained haplotypes of 16S and ITS in this study. (DOCX 16 kb

Additional file 1: of Diversity of the Bosmina (Cladocera: Bosminidae) in China, revealed by analysis of two genetic markers (mtDNA 16S and a nuclear ITS)

Table S1. Numbers of observed haplotypes (of the 16S and ITS) in the investigated Chinese waterbodies; Table S2. The waterbodies where Bosmina was not found; Table S3. List of GenBank reference clones from Japanese, North American, European, Southern and Central Asian specimens used in phylogenetic analyses and haplotype networks. (DOCX 27 kb

Effect of galectin-9 treatment on cellular infiltration in spleen of Con A treated mice.

<p>Galectin-9 (100 µg per mouse) or PBS was administrated i.v. to Balb/c mice (n = 8 per group) 30 min before Con A injection (20 mg kg^–1). The splenocytes were isolated 24 h later. Percentages and phenotype (surface TIM-3) of CD4⁺ T cells in spleen of mice are shown in (A). (B) The frequencies of Th1, Th17 and Treg subsets were detected by FACS. Statistically significant differences were indicated in (C). The results (A, C) were presented as the mean ± SD of three separate experiments. **, p<0.01; *, p<0.05 vs PBS treatment.</p

Feeding Single-Walled Carbon Nanotubes or Graphene to Silkworms for Reinforced Silk Fibers

Silkworm silk is gaining significant attention from both the textile industry and research society because of its outstanding mechanical properties and lustrous appearance. The possibility of creating tougher silks attracts particular research interest. Carbon nanotubes and graphene are widely studied for their use as reinforcement. In this work, we report mechanically enhanced silk directly collected by feeding Bombyx mori larval silkworms with single-walled carbon nanotubes (SWNTs) and graphene. We found that parts of the fed carbon nanomaterials were incorporated into the as-spun silk fibers, whereas the others went into the excrement of silkworms. Spectroscopy study indicated that nanocarbon additions hindered the conformation transition of silk fibroin from random coil and α-helix to β-sheet, which may contribute to increased elongation at break and toughness modules. We further investigated the pyrolysis of modified silk, and a highly developed graphitic structure with obviously enhanced electrical conductivity was obtained through the introduction of SWNTs and graphene. The successful generation of these SWNT- or graphene-embedded silks by in vivo feeding is expected to open up possibilities for the large-scale production of high-strength silk fibers

Laser-Heating Effect on Raman Spectra of Individual Suspended Single-Walled Carbon Nanotubes

We studied the Raman spectra of 21 individual suspended single-walled carbon nanotubes (SWNTs) using different excitation laser powers. The results indicate that the laser-heating effect is more significant for suspended SWNT than nanotubes sitting on a substrate. The spectral variations of these individual SWNTs induced by different laser power shed new light on the temperature dependence of Raman spectra and electronic properties of SWNTs. By analyzing the frequency downshift of each nanotube induced by increased laser power, the temperature coefficient of radial breathing mode (RBM) frequency ωRBM is supposed to be diameter- and chirality-dependent, whereas that of the G-band frequency ωG+ is not. The behaviors of full width at half-maximum (fwhm) and intensity ratio between anti-Stokes and Stokes spectra (IAS/IS) of RBM with increasing laser power reflected the temperature increase and the consequent variation in the electronic density of states (DOS) of SWNT. The variation of resonance intensity with laser power showed interesting dependence on Eii > Elaser or Eii Elaser, suggesting downshift of Eii with increased temperature, which offers the possibility of utilizing the optical/thermal response of SWNT to modulate the electronic property of nanotubes