In this study, carbon nanotube (CNT) hybrid aerogels with high mechanical properties were fabricated by interconnecting structural networks of CNTs using poly(vinyl alcohol) (PVA) through ...amine-functionalized iron oxide (NH2-Fe). Consequently, Fe-CNT-PVA hybrid aerogels exhibited good structural stabilities, even under repeated loads due to the interconnection bonding with PVA between neighboring CNTs. Furthermore, compared to the Fe-CNT aerogels, the Fe-CNT-PVA hybrid aerogels showed ∼3 times higher specific surfaces due to the tuning of the internal morphology by controlling electromagnetic interactions between NH2-Fe on the surface of the CNTs and the applied magnetic field. These results clearly show that CNT aerogels with both improved structural stabilities and specific surface areas can be fabricated by the method proposed in this study.
In this paper, we develop a density evolution (DE) framework for analyzing the iterative joint decoding (JD) for non-orthogonal multiple access (NOMA) systems, where the ordered-statistics decoding ...(OSD) is applied to decode short block codes. We first investigate the density-transform feature of the soft-output OSD (SOSD), by deriving the density of the extrinsic log-likelihood ratio (LLR) with known densities of the priori LLR. Then, we represent the OSD-based JD by bipartite graphs (BGs), and develop the DE framework by characterizing the density-transform features of nodes over the BG under the binary phase shift keying (BPSK) transmission. Numerical examples show that the proposed DE framework accurately tracks the evolution of LLRs during the iterative decoding, especially at moderate-to-high SNRs. Based on the DE framework, we further analyze the BER performance of the OSD-based JD, and the convergence points of the two-user and equal-power systems.
Enterococcus faecalis
, a Gram-positive bacterium commonly isolated in patients with refractory apical periodontitis, invades dentin tubules easily and forms biofilms. Bacteria in biofilms, which ...contribute to recurrent and/or chronic inflammatory diseases, are more resistant to antimicrobial agents than planktonic cells and easily avoid phagocytosis. Although
Lactobacillus plantarum
lipoteichoic acid (Lp.LTA) is associated with biofilm formation, the effect of Lp.LTA on biofilm formation by
E. faecalis
is not clearly understood. In this study, we investigated whether Lp.LTA inhibits
E. faecalis
biofilm formation. The degree of biofilm formation was determined by using crystal violet assay and LIVE/DEAD bacteria staining. The quantification of bacterial growth was determined by measuring the optical density at 600 nm with a spectrophotometer. Formation of biofilms on human dentin slices was observed under a scanning electron microscope.
E. faecalis
biofilm formation was reduced by Lp.LTA treatment in a dose-dependent manner. Lp.LTA inhibited biofilm development of
E. faecalis
at the early stage without affecting bacterial growth. LTA from other
Lactobacillus
species such as
Lactobacillus acidophilus, Lactobacillus casei
, or
Lactobacillus rhamnosus
GG also inhibited
E. faecalis
biofilm formation. In particular, among LTAs from various lactobacilli, Lp.LTA showed the highest inhibitory effect on biofilms formed by
E. faecalis
. Interestingly, LTAs from lactobacilli could remove the biofilm preformed by
E. faecalis
. These inhibitory effects were also observed on the surface of human dentin slices. In conclusion, Lactobacillus species LTA inhibits biofilm formation caused by
E. faecalis
and it could be used as an anti-biofilm agent for prevention or treatment against
E. faecalis
-associated diseases.
Fibers of long-fiber-reinforced thermoplastic (LFT) pellets are longer than those of short-fiber-reinforced thermoplastic (SFT) pellets produced by extrusion. To overcome the fiber length limitations ...of the SFT pellets, LFT pellets were prepared by a pultrusion process using continuous fibers, which afforded longer fibers. Currently, long glass-fiber-reinforced polypropylene (LGF-PP) materials, which are one of the growing markets of the plastics industry, are typically used, particularly for applications in the automotive industry where lightweight performance and cost savings are required. The LFT pellets are primarily converted into the final product by injection molding. During the injection molding process, the LFT pellets are broken and the fiber length decreases as a consequence. In this study, glass and carbon-fiber-reinforced polypropylene of various pellet lengths (3-16 mm) were prepared by impregnating pultrusion process to evaluate the effect of mechanical properties according to fiber length. The length of the residual fibers recorded after injection molding were observed to decrease in proportion to the pellet length. Even with LFTs having the same material composition, the mechanical properties was different after injection molding according to the residual fiber length. In this injection molded LFT, the flexural modulus was higher as the residual fiber length was shorter. The impact strength was larger in samples without adhesive resin and the observed differences were larger for longer fiber lengths. From these results, the mechanical properties of LFT can be improved by understanding the properties of long fibers.
Chemosensory-related gene (CRG) families have been studied extensively in insects, but their evolutionary history across the Arthropoda had remained relatively unexplored. Here, we address current ...hypotheses and prior conclusions on CRG family evolution using a more comprehensive data set. In particular, odorant receptors were hypothesized to have proliferated during terrestrial colonization by insects (hexapods), but their association with other pancrustacean clades and with independent terrestrial colonizations in other arthropod subphyla have been unclear. We also examine hypotheses on which arthropod CRG family is most ancient. Thus, we reconstructed phylogenies of CRGs, including those from new arthropod genomes and transcriptomes, and mapped CRG gains and losses across arthropod lineages. Our analysis was strengthened by including crustaceans, especially copepods, which reside outside the hexapod/branchiopod clade within the subphylum Pancrustacea. We generated the first high-resolution genome sequence of the copepod Eurytemora affinis and annotated its CRGs. We found odorant receptors and odorant binding proteins present only in hexapods (insects) and absent from all other arthropod lineages, indicating that they are not universal adaptations to land. Gustatory receptors likely represent the oldest chemosensory receptors among CRGs, dating back to the Placozoa. We also clarified and confirmed the evolutionary history of antennal ionotropic receptors across the Arthropoda. All antennal ionotropic receptors in E. affinis were expressed more highly in males than in females, suggestive of an association with male mate-recognition behavior. This study is the most comprehensive comparative analysis to date of CRG family evolution across the largest and most speciose metazoan phylum Arthropoda.
We report an effective way to fabricate mechanically strong and multifunctional polyimide (PI) nanocomposites using aminophenyl functionalized graphene nanosheet (APGNS). APGNS was successfully ...obtained through a diazonium salt reaction. PI composites with different loading of APGNS were prepared by in situ polymerization. Both the mechanical and electrical properties of the APGNS/PI composites were significantly improved compared with those of pure PI due to the homogeneous dispersion of APGNS and the strong interfacial covalent bonds between APGNS and the PI matrix. The electrical conductivity of APGNS/PI (3:97 w/w) was 6.6 × 10–2 S/m which was about 1011 times higher than that of pure PI. Furthermore, the modulus of APGNS/PI was increased up to 16.5 GPa, which is approximately a 610% enhancement compared to that of pure PI, and tensile strength was increased from 75 to 138 MPa. The water vapor transmission rate of APGNS/PI composites (3:97 w/w) was reduced by about 74% compared to that of pure PI.
A two-step plant regeneration has been widely exploited to genetic manipulation and genome engineering in plants. Despite technical importance, understanding of molecular mechanism underlying in ...vitro plant regeneration remains to be fully elucidated. Here, we found that the HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENES 1 (HOS1)-PHYTOCHROME INTERACTING FACTOR 4/5 (PIF4/5) module participates in callus formation. Consistent with the repressive role of HOS1 in PIF transcriptional activation activity, hos1-3 mutant leaf explants exhibited enhanced callus formation, whereas pif4-101 pif5-3 mutant leaf explants showed reduced callus size. The HOS1-PIF4/5 function would be largely dependent on auxin biosynthesis and signaling, which are essential for callus initiation and proliferation. Our findings suggest that the HOS1-PIF4/5 module plays a pivotal role in auxin-dependent callus formation in Arabidopsis.
1α,25(OH)(2)D(3), the active form of vitamin D(3), has been reported to regulate the cell biology of skeletal muscle. However, there has been some controversy about the expression of the vitamin D ...receptor (VDR) and thus the potential role of vitamin D(3) in skeletal muscle. In this study, we isolated and sequenced the full-length Vdr and Cyp27b1 transcripts in C2C12 myoblasts and myotubes. Western blots and immunocytochemistry confirmed protein expression in both myoblasts and myotubes clearly demonstrating that C2C12 cells express VDR and CYP27B1. To determine the vitamin D(3) action, we found that C2C12 myoblasts treated with either 1α,25(OH)(2)D(3) or 25(OH)D(3) inhibited cell proliferation and this was associated with increased Vdr expression. The observation that treatment of C2C12 myoblasts with the inactive form of vitamin D(3), 25(OH)D(3), inhibited proliferation suggested that CYP27B1 was functionally active. We used small interfering RNA to knock down Cyp27b1 in myoblasts, and cells were treated with 25(OH)D(3). The growth-suppressive effects of 25(OH)D(3) were abolished, suggesting that CYP27B1 in myoblasts is necessary for the ability of 25(OH)D(3) to affect cell proliferation. Finally, we analyzed expression of VDR and CYP27B1 in regenerating skeletal muscle in vivo. We found that expression of VDR and CYP27B1 increased significantly at day 7 of regeneration, and these results confirm the expression of Vdr and Cyp27b1 in vivo and suggest a potential role for vitamin D(3) in skeletal muscle regeneration following injury.
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