A Comparison of PKD2L1-Expressing Cerebrospinal Fluid Contacting Neurons in Spinal Cords of Rodents, Carnivores, and Primates.

Cerebrospinal fluid contacting neurons (CSF-cNs) are a specific type of neurons located around the ventricles in the brain and the central canal in the spinal cord and have been demonstrated to be intrinsic sensory neurons in the central nervous system. One of the important channels responsible for the sensory function is the polycystic kidney disease 2-like 1 (PKD2L1) channel. Most of the studies concerning the distribution and function of the PKD2L1-expressing CSF-cNs in the spinal cord have previously been performed in non-mammalian vertebrates. In the present study immunohistochemistry was performed to determine the distribution of PKD2L1-immunoreactive (IR) CSF-cNs in the spinal cords of four mammalian species: mouse, rat, cat, and macaque monkey. Here, we found that PKD2L1-expressing CSF-cNs were present at all levels of the spinal cord in these animal species. Although the distribution pattern was similar across these species, differences existed. Mice and rats presented a clear PKD2L1-IR cell body labeling, whereas in cats and macaques the PKD2L1-IR cell bodies were more weakly labeled. Ectopic PKD2L1-IR neurons away from the ependymal layer were observed in all the animal species although the abundance and the detailed locations varied. The apical dendritic protrusions with ciliated fibers were clearly seen in the lumen of the central canal in all the animal species, but the sizes of protrusion bulbs were different among the species. PKD2L1-IR cell bodies/dendrites were co-expressed with doublecortin, MAP2 (microtubule-associated protein 2), and aromatic L-amino acid decarboxylase, but not with NeuN (neuronal nuclear protein), indicating their immature properties and ability to synthesize monoamine transmitters. In addition, in situ hybridization performed in rats revealed PKD2L1 mRNA expression in the cells around the central canal. Our results indicate that the intrinsic sensory neurons are conserved across non-mammalian and mammalian vertebrates. The similar morphology of the dendritic bulbs with ciliated fibers (probably representing stereocilia and kinocilia) protruding into the central canal across different animal species supports the notion that PKD2L1 is a chemo- and mechanical sensory channel that responds to mechanical stimulations and maintains homeostasis of the spinal cord. However, the differences of PKD2L1 distribution and expression between the species suggest that PKD2L1-expressing neurons may receive and process sensory signals differently in different animal species.

Nanometer effect promoting arsenic removal on α-MnO2 nano-surface in aqueous solution: DFT+U research.

The nanometer effect in the process of arsenic ions removal on α-MnO2 nano-surface is studied by the first-principle method through microfacet models. Several parameters, such as adhesion energy, electrostatic potential, and Mulliken population were calculated to illuminate the internal mechanism. The results show that the adsorption energies of As(OH)3 molecules on MnO2[(100×110)] nanostructure are smaller than that on the bulk surface with the same concentration, which means the nanometer effect is beneficial to enhance the adsorption ability of MnO2 nano-surface. In an aqueous solution, there exist two possible removal ways of As ions. One is the direct reaction of As(OH)3→As(OH)6-, which occurs both in bulk surface and nano-surface. However, to nanomaterials, there exists another removal way of As(OH)3→As(OH)4→As(OH)6- through an intermediate As(OH)4 molecule produced by nanometer effect. Furthermore the smaller electrostatic potential of As ions on [(100×110)] nano-surface is beneficial to enhance the removal capability of As ions. Then the reason why MnO2 nanomaterials have better catalytic activity than the bulk materials is originated from its much less adhesion energy, much more removal ways, and much smaller electrostatic potential. So this research provides a detailed understanding of the removal capability of toxic ions influenced by a nanometer effect.

Insight into the surface activity of defect structure in α-MnO2 nanorod: first-principles research.

The contribution of defect structure to the catalytic property of α-MnO2 nanorod still keeps mysterious right now. Using microfacet models representing defect structure and bulk models with high Miller index, several parameters, such as cohesive energy, surface energy, density of state, electrostatic potential, et al., have been used to investigate the internal mechanism of their chemical activities by first-principles calculation. The results show that the trend in surface energies of microfacet models follows as Esurface[(112 × 211)] > Esurface[(110 × 211)] > Esurface[(100 × 211)] > Esurface[(111 × 211)] > Esurface[(112 × 112)] > Esurface[(111 × 112)], wherein all of them are larger than that of bulk models. So the chemical activity of defect structure is much more powerful than that of bulk surface. Deep researches on electronic structure show that the excellent chemical activity of microfacet structure has larger value in dipole moments and electrostatic potential than that of bulk surface layer. And the microfacet models possess much more peaks of valent electrons in deformantion electronic density and molecular orbital. Density of state indicates that the excellent chemical activity of defect structure comes from their proper hybridization in p and d orbitals.

Hydrogen-substituted graphdiyne/graphene as an sp/sp2 hybridized carbon interlayer for lithium-sulfur batteries.

To overcome the shuttle effect in lithium-sulfur (Li-S) batteries, an sp/sp2 hybridized all-carbon interlayer by coating graphene (Gra) and hydrogen-substituted graphdiyne (HsGDY) with a specific surface area as high as 2184 m2 g-1 on a cathode is designed and prepared. The two-dimensional network and rich pore structure of HsGDY can enable the fast physical adsorption of lithium polysulfides (LiPSs). In situ Raman spectroscopy and ex situ X-ray photoelectron spectroscopy (XPS) combined with density functional theory (DFT) computations confirm that the acetylenic bonds in HsGDY can trap the Li+ of LiPSs owing to the strong adsorption of Li+ by acetylenic active sites. The strong physical adsorption and chemical anchoring of LiPSs by the HsGDY materials promote the conversion reaction of LiPSs to further mitigate the shuttling problem. As a result, Li-S batteries integrated with the all-carbon interlayers exhibit excellent cycling stability during long-term cycling with an attenuation rate of 0.089% per cycle at 1 C over 500 cycles.

Research on the removal mechanism of antimony on α-MnO2 nanorod in aqueous solution: DFT + U method.

Although previous papers have reported the desorption process of antimony (Sb) ions adsorbed on α-MnO2 nanomaterials, some trace Sb(OH)4- molecular observed in experiments have not been understood clearly. Using two models as popular bulk surface and new microfacet, several parameters, such as adsorption energy, bond length, total density of state (TDOS) and activation energy, were calculated to research and analyze the catalytic reaction of Sb oxides on α-MnO2. The results show that the bulk surface model has the "mirror effect" in revealing the catalytic property of α-MnO2 nanorods. Using MnO2[(100 × 110)] microfacet model, a new molecular Sb(OH)4- molecular appears in the reaction process of Sb(OH)3 + H2O → Sb(OH)4- + H+. Further comparing the geometric morphology and TDOS of Sb(OH)4- with Sb(OH)6- molecular, it is found that their bonding length, dihedral and energy orbital of bonding peaks are too close to set the Sb(OH)4- as the precursor product of Sb(OH)6- molecular. Then the desorption process of Sb ions on α-MnO2 nanorods is virtually transformed into Sb(OH)3 → Sb(OH)4-  → Sb(OH)6- way in aqueous solution. Thus, our findings open an avenue for detailed and comprehensive theoretical studies of catalytic reaction by nanomaterials.

Fast photoelectro-reduction of CrVI over MoS2@TiO2 nanotubes on Ti wire.

A stable MoS2 nanosheets@TiO2 NTAs composite was prepared via a simple hydrothermal process. Few-layer MoS2 nanosheets distributed on the TiO2 nanotube top surface and the inner walls rather than filling in the tubes, allowing abundant tubular channels open to environment and benefiting for efficient mass transport. Photocatalytic (PE) and photoelectrocatalytic (PEC) performance of the composite were evaluated on CrVI reduction, with variable low molecule weight organic acids (LOAs) added as sacrificial electron donor to form a charge-transfer-complex (CTC) between LOAs and TiO2/MoS2, which is sensitive to the visible light illumination and could induce the photo-reduction of CrVI and photo-oxidation of LOAs. The overall trend of CrVI PEC rates are in the order as: L(+)-Tartaric acid>oxalic acid>citric acid>malic acid>amber acid, which is 103.9>62.5>31.2>21.6>2.5mg/Lmin-1cm-2, respectively. The improved catalytic performance and excellent stability of the composite can be attributed to the abundant active adsorption and reaction sites on MoS2 nanosheets and the formation of a heterojunction between TiO2 and MoS2. Moreover, the appropriate application of LOAs and voltage also have a great contribution to the utilization of sunlight and efficient separation of photogenerated carriers.

MiR-124 Promotes Newborn Olfactory Bulb Neuron Dendritic Morphogenesis and Spine Density.

Using microarray analysis, we detected microRNA-124 (miR-124) to be abundantly expressed in the olfactory bulb (OB). miR-124 regulates adult neurogenesis in the subventricular zone (SVZ). However, much less is known about its role in newborn OB neurons. Here, using both gain-of-function and loss-of-function approaches, we demonstrate that brain-specific miR-124 affects dendritic morphogenesis and spine density in newborn OB neurons. Functional Annotation Clustering of miR-124 targets was enriched in "cell morphogenesis involved in neuron differentiation."

Synthesis of YSZ@Ni Nanoparticle by Modified Electroless Plating Process.

Ni-YSZ (Y2O3-stabilized ZrO2) composites with core-shell structure (YSZ@Ni) were produced by modified electroless plating process. It was found that YSZ nanoparticles were well encapsulated by nickel powders at 65 degrees C with pH = 12. The spherical nanopowders had core-shell structure and the shell layer was less than 20 nm. The X-ray diffraction (XRD) analysis inferred the production was composed of YSZ and Ni crystals. In the end, the formation mechanism was discussed.

Formaldehyde exposure alters miRNA expression profiles in the olfactory bulb.

It has been reported that inhaling formaldehyde (FA) causes damage to the central nervous system. However, it is unclear whether FA can disturb the function of the olfactory bulb. Using a microarray, we found that FA inhalation altered the miRNA expression profile. Functional enrichment analysis of the predicted targets of the changed miRNA showed that the enrichment canonical pathways and networks associated with cancer and transcriptional regulation. FA exposure disrupts miRNA expression profiles within the olfactory bulb.

Sulfur-doped graphene as an efficient metal-free cathode catalyst for oxygen reduction.

Tailoring the electronic arrangement of graphene by doping is a practical strategy for producing significantly improved materials for the oxygen-reduction reaction (ORR) in fuel cells (FCs). Recent studies have proven that the carbon materials doped with the elements, which have the larger (N) or smaller (P, B) electronegative atoms than carbon such as N-doped carbon nanotubes (CNTs), P-doped graphite layers and B-doped CNTs, have also shown pronounced catalytic activity. Herein, we find that the graphenes doped with the elements, which have the similar electronegativity with carbon such as sulfur and selenium, can also exhibit better catalytic activity than the commercial Pt/C in alkaline media, indicating that these doped graphenes hold great potential for a substitute for Pt-based catalysts in FCs. The experimental results are believed to be significant because they not only give further insight into the ORR mechanism of these metal-free doped carbon materials, but also open a way to fabricate other new low-cost NPMCs with high electrocatalytic activity by a simple, economical, and scalable approach for real FC applications.