Inhibition of kinetic random-distribution in DNA Seesaw gates and biosensors for complete leakage prevention.

DNA nanomaterials have a wide application prospect in biomedical field, among which DNA computers and biosensors based on Seesaw-based DNA circuit is considered to have the most development potential. However, the serious leakage of Seesaw-based DNA circuit prevented its further development and application. Moreover, the existing methods to suppress leakage can't achieve the ideal effect.

Probing the Representational Structure of Regular Polysemy via Sense Analogy Questions: Insights from Contextual Word Vectors.

Regular polysemes are sets of ambiguous words that all share the same relationship between their meanings, such as CHICKEN and LOBSTER both referring to an animal or its meat. To probe how a distributional semantic model, here exemplified by bidirectional encoder representations from transformers (BERT), represents regular polysemy, we analyzed whether its embeddings support answering sense analogy questions similar to "is the mapping between CHICKEN (as an animal) and CHICKEN (as a meat) similar to that which maps between LOBSTER (as an animal) to LOBSTER (as a meat)?" We did so using the LRcos model, which combines a logistic regression classifier of different categories (e.g.

Oxygen Evolution Reaction in Energy Conversion and Storage: Design Strategies Under and Beyond the Energy Scaling Relationship.

The oxygen evolution reaction (OER) is the essential module in energy conversion and storage devices such as electrolyzer, rechargeable metal-air batteries and regenerative fuel cells. The adsorption energy scaling relations between the reaction intermediates, however, impose a large intrinsic overpotential and sluggish reaction kinetics on OER catalysts. Developing advanced electrocatalysts with high activity and stability based on non-noble metal materials is still a grand challenge.

Word Senses as Clusters of Meaning Modulations: A Computational Model of Polysemy.

Most words in natural languages are polysemous; that is, they have related but different meanings in different contexts. This one-to-many mapping of form to meaning presents a challenge to understanding how word meanings are learned, represented, and processed. Previous work has focused on solutions in which multiple static semantic representations are linked to a single word form, which fails to capture important generalizations about how polysemous words are used; in particular, the graded nature of polysemous senses, and the flexibility and regularity of polysemy use.

Boosted Oxygen Evolution Reactivity by Igniting Double Exchange Interaction in Spinel Oxides.

A double-exchange interaction (DEI) was demonstrated to boost the oxygen evolution reaction (OER) in spinel oxides. DEI was ignited by synergistic actions of constructing nanoheterojunctions and creating oxygen vacancy (V) in spinel NiCoO. DEI between octahedrally coordinated Ni and Co resulted in the generation of superior OER active centers Co and Ni.

Photoelectrochemical overall water splitting with textured CuBiO as a photocathode.

Nanotextured CuBi2O4 photocathodes have been developed for applications toward solar water splitting. Tailoring the CuBi2O4 photocathodes to yield a high photocurrent and a positively large onset potential demonstrates their applicability in a photoelectrochemical tandem cell for entirely solar-driven overall water splitting.

Study of the inorganic substitution in a functionalized UiO-66 metal-organic framework.

In this study the band gap modulation was studied in response to inorganic ion substitution within a thermally stable UiO-66 metal-organic framework (MOF). A combination of density functional theory prediction in conjunction with experimental predictions were used to map out the complete composition space for three inorganic ions (Zr, Ti, Hf) and three functional groups. The three functional groups include an amino group (NH2), a nitro group (NO2), and a hydrogenated case (H).

Solar hydrogen generation by a CdS-Au-TiO2 sandwich nanorod array enhanced with Au nanoparticle as electron relay and plasmonic photosensitizer.

This paper presents a sandwich-structured CdS-Au-TiO2 nanorod array as the photoanode in a photoelectrochemical cell (PEC) for hydrogen generation via splitting water. The gold nanoparticles sandwiched between the TiO2 nanorod and the CdS quantum dot (QD) layer play a dual role in enhancing the solar-to-chemical energy conversion efficiency. First, the Au nanoparticles serve as an electron relay, which facilitates the charge transfer between CdS and TiO2 when the CdS QDs are photoexcited by wavelengths shorter than 525 nm.

Plasmon-induced photonic and energy-transfer enhancement of solar water splitting by a hematite nanorod array.

Plasmonic metal nanostructures offer a promising route to improve the solar energy conversion efficiency of semiconductors. Here we show that incorporation of a hematite nanorod array into a plasmonic gold nanohole array pattern significantly improves the photoelectrochemical water splitting performance, leading to an approximately tenfold increase in the photocurrent at a bias of 0.23 V versus Ag|AgCl under simulated solar radiation.

Solar hydrogen generation by nanoscale p-n junction of p-type molybdenum disulfide/n-type nitrogen-doped reduced graphene oxide.

Molybdenum disulfide (MoS2) is a promising candidate for solar hydrogen generation but it alone has negligible photocatalytic activity. In this work, 5-20 nm sized p-type MoS2 nanoplatelets are deposited on the n-type nitrogen-doped reduced graphene oxide (n-rGO) nanosheets to form multiple nanoscale p-n junctions in each rGO nanosheet. The p-MoS2/n-rGO heterostructure shows significant photocatalytic activity toward the hydrogen evolution reaction (HER) in the wavelength range from the ultraviolet light through the near-infrared light.

SnO₂@CdS nanowire-quantum dots heterostructures: tailoring optical properties of SnO₂ for enhanced photodetection and photocatalysis.

Rationally designed SnO2@CdS nanowire-quantum dots (QDs) heterostructures were realized by a wet-chemical method via hydroxide cluster growth mechanism on high crystalline quality SnO2 nanowires, which were synthesized by a vapor transport method. The heterostructures showed enhanced photon harvesting capability and photodetection sensitivity at visible regime than that of wide band gap homogeneous SnO2 nanowires, as characterized by UV-Vis absorption and photoconductivity measurements. In addition, the SnO2@CdS nanowire-QDs heterostructures showed enhanced photocatalytic activity by more than 109% in a conceptual demonstration of photodegradation of methylene blue solution.

Nanostructured carbon-metal oxide composite electrodes for supercapacitors: a review.

This paper presents a review of the research progress in the carbon-metal oxide composites for supercapacitor electrodes. In the past decade, various carbon-metal oxide composite electrodes have been developed by integrating metal oxides into different carbon nanostructures including zero-dimensional carbon nanoparticles, one-dimensional nanostructures (carbon nanotubes and carbon nanofibers), two-dimensional nanosheets (graphene and reduced graphene oxides) as well as three-dimensional porous carbon nano-architectures. This paper has described the constituent, the structure and the properties of the carbon-metal oxide composites.

Differential mouse pulmonary dose and time course responses to titanium dioxide nanospheres and nanobelts.

Three anatase titanium dioxide (TiO(2)) nanoparticles (NPs) were prepared; nanospheres (NSs), short nanobelts (NB1), and long nanobelts (NB2). These NPs were used to investigate the effect of NP shape and length on lung toxicity. Mice were exposed (0-30 µg per mouse) by pharyngeal aspiration and pulmonary toxicity was assessed over a 112-day time course.

Photocatalytic activity enhanced by plasmonic resonant energy transfer from metal to semiconductor.

Plasmonic metal nanostructures have been incorporated into semiconductors to enhance the solar-light harvesting and the energy-conversion efficiency. So far the mechanism of energy transfer from the plasmonic metal to semiconductors remains unclear. Herein the underlying plasmonic energy-transfer mechanism is unambiguously determined in Au@SiO(2)@Cu(2)O sandwich nanostructures by transient-absorption and photocatalysis action spectrum measurement.

Photoelectrochemical performance enhanced by a nickel oxide-hematite p-n junction photoanode.

A p-n junction photoanode has been fabricated by depositing p-type NiO nanoparticles on the n-type hematite thin film. Such a photoanode is employed for a photoelectrochemical cell. NiO not only facilitates the extraction of accumulated holes from hematite via the p-n junction, but also lowers the barrier for oxygen evolution reaction.

Microsomal glutathione transferase 1 protects against toxicity induced by silica nanoparticles but not by zinc oxide nanoparticles.

Microsomal glutathione transferase 1 (MGST1) is an antioxidant enzyme located predominantly in the mitochondrial outer membrane and endoplasmic reticulum and has been shown to protect cells from lipid peroxidation induced by a variety of cytostatic drugs and pro-oxidant stimuli. We hypothesized that MGST1 may also protect against nanomaterial-induced cytotoxicity through a specific effect on lipid peroxidation. We evaluated the induction of cytotoxicity and oxidative stress by TiO(2), CeO(2), SiO(2), and ZnO in the human MCF-7 cell line with or without overexpression of MGST1.

Water-soluble superparamagnetic magnetite nanoparticles with biocompatible coating for enhanced magnetic resonance imaging.

Ultrasmall superparamagnetic Fe(3)O(4) nanoparticles (USIRONs) were synthesized by a novel, easily scalable chemical reduction of colloidal iron hydroxide under hydrothermal conditions. The average crystallite size (5.1 ± 0.

A two-step surface modification approach for Au and CdS NPs loaded mesoporous thin films and the greatly enhanced optical nonlinearity.

A new two-step surface modification approach has been developed for the incorporation of both CdS and Au NPs into the pore channels of silica mesoporous thin films. The composite thin films were investigated by FTIR, UV-vis, XRD and SEM, the results confirmed that the semiconductor and metal NPs were successfully incorporated with uniform particle size and high dispersivity thanks to the confinement effect of mesoporous thin films. The nonlinear optical susceptibility was measured by the Z-scan technique.

Stepwise in situ synthesis and characterization of metallophthalocyanines@mesoporous matrix SBA-15 composites.

The successful in situ synthesis of metallophthalocyanines in mesoporous matrices is presented in this report. To overcome the high hydrophobicity of phthalocyanine (Pc) compounds in conventional wet chemical methods, a simple but effective route is developed to incorporate the metallophthalocyanines into the mesoporous matrix via an in situ reaction process between pre-loaded metal ions and 1,2-dicyanobenzene (DCB) introduced by chemical vapor deposition. The Pcs are not directly loaded into the pores, but the precursors of metallophthalocyanines (metal ions and small DCB molecules) are introduced stepwise into the pore channels, which are then used as 'micro-reactors" to produce incorporated MePcs by in situ reactions.

Donor-pi-acceptor structure between Ag nanoparticles and azobenzene chromophore and its enhanced third-order optical non-linearity.

An amorphous silica hybrid film containing covalently linked azobenzene chromophores and Ag nanoparticles was synthesized by a one-step sol-gel route in the presence of amino trialkoxysilane (APTES). The electron transfer from the N-containing groups in the APTES and azobenzene molecules, which are chemisorbed onto the surface of Ag nanoaprticles, makes the Ag nanoparticles negatively charged. Subsequently, a new D-pi-A electron structure between the Ag nanoparticles and the N-containing groups/azobenzene chromophores is created.

Functional evolution within a protein superfamily.

The ability to predict and characterize distributions of reactivities over families and even superfamilies of proteins opens the door to an array of analyses regarding functional evolution. In this article, insights into functional evolution in the Kazal inhibitor superfamily are gained by analyzing and comparing predicted association free energy distributions against six serine proteinases, over a number of groups of inhibitors: all possible Kazal inhibitors, natural avian ovomucoid first and third domains, and sets of Kazal inhibitors with statistically weighted combinations of residues. The results indicate that, despite the great hypervariability of residues in the 10 proteinase-binding positions, avian ovomucoid third domains evolved to inhibit enzymes similar to the six enzymes selected, whereas the orthologous first domains are not inhibitors of these enzymes on purpose.

Analysis of sequence-reactivity space for protein-protein interactions.

Sequence-reactivity space is defined by the relationships between amino acid type choices at some residue positions in a protein and the reactivities of the resulting variants. We are studying Kazal superfamily serine proteinase inhibitors, under substitution of any combination of residue types at 10 binding-region positions. Reactivities are defined by the standard free energy of association for an inhibitor against an enzyme, and we are interested in both the strength (the free energy value) and specificity (relative free energy values for one inhibitor against different enzymes).