Heterostrain-Induced Zeeman-like Splitting in h-BN-Encapsulated Bilayer WSe2.

Heterostrain is predicted to induce exceptionally rich physics in atomically thin two-dimensional structures by modifying the symmetry and optical selection rules. In this work, we introduce heterostrain into WSe2 bilayers by combining h-BN encapsulation and high-temperature vacuum annealing. Nonvolatile heterostrain gives rise to a Zeeman-like splitting associated with the elliptically polarized optical emission of interlayer K-K excitons. Further manipulation of the interlayer exciton emission in an external magnetic field reveals that the Zeeman-like splitting cannot be eliminated even in a magnetic field of up to ±6 T. We propose a microscopic picture with respect to the layer and valley pseudospin to interpret the results. Our findings imply an intriguing way to encode binary information with the layer pseudospin enabled by the heterostrain and open a venue for manipulating the layer pseudospin with heterostrain engineering, optical pseudospin injection, and an external magnetic field.

Self-Generation of Distinguishable Fluorescent Probes via a One-Pot Process for Multiple MicroRNA Detection by Liquid Chromatography.

To address the challenge of signal production and separation for multiple microRNA (miRNA) detection, in this work, a "one-pot" process to self-generate distinguishable fluorescent probes was developed. Based on a long and short probe amplification strategy, the generated G-quadruplex fluorescent dye-free probes can be separated and detected by a high-performance liquid chromatography-fluorescence platform. The free hairpin probes enriched in guanine with different lengths and base sequences were designed and could be opened by the target miRNAs (miRNA-10b, miRNA-21, and miRNA-210). Cleaved G-quadruplex probes with fluorescent signal could be generated in a one-pot process after a duplex-specific nuclease-based cleavage, and the detection of multiple miRNAs could be realized in one run. No solid nanomaterials were applied in the assay, which avoided the blocking of the column. Moreover, without modification of expensive fluorescein, the experimental cost was greatly reduced. The one-pot reaction process also eliminated tedious preparation steps and suggested feasibility of automation. The limits of detection of miRNA-10b, miRNA-21, and miRNA-210 were 2.19, 2.20, and 2.75 fM, respectively. Notably, this method was successfully applied to multiplex detection of miRNAs in serum samples from breast cancer patients within 30 min.

Homology-modeled ligand-binding domains of medaka estrogen receptors and androgen receptors: a model system for the study of reproduction.

Estrogen and androgen and their receptors play critical roles in physiological processes such as sexual differentiation and development. Using the available structural models for the human estrogen receptors alpha and beta and androgen receptor as templates, we designed in silico agonist and antagonist models of medaka estrogen receptor (meER) alpha, beta-1, and beta-2, and androgen receptor (meAR) alpha and beta. Using these models, we studied (1) the structural relationship between the ligand-binding domains (LBDs) of ERs and ARs of human and medaka, and (2) whether medaka ER and AR can be potential models for studying the ligand-binding activities of various agonists and antagonists of these receptors by docking analysis. A high level of conservation was observed between the sequences of the ligand-binding domains of meERalpha and huERalpha, meERbeta1 and huERbeta, meERbeta2, and huERbeta with 62.8%, 66.4%, and 65.1% identity, respectively. The sequence conservation between meARalpha and huAR, meARbeta, and huAR was found with 70.1% and 61.0% of identity, respectively. Thirty-three selected endocrine disrupting chemicals (EDCs), including both agonists and antagonists, were docked into the LBD of ER and AR, and the corresponding docking score for medaka models and human templates were calculated. In order to confirm the conservation of the overall geometry and the binding pocket, the backbone root mean square deviation (RMSD) for Calpha atoms was derived from the structure superposition of all 10 medaka homology models to the six human templates. Our results suggested conformational conservation between the ERs and ARs of medaka and human, Thus, medaka could be highly useful as a model system for studies involving estrogen and androgen interaction with their receptors.