Discovery of enhanced lattice dynamics in a single-layered hybrid perovskite.

Layered hybrid perovskites exhibit emergent physical properties and exceptional functional performances, but the coexistence of lattice order and structural disorder severely hinders our understanding of these materials. One unsolved problem regards how the lattice dynamics are affected by the dimensional engineering of the inorganic frameworks and their interaction with the molecular moieties. Here, we address this question by using a combination of spontaneous Raman scattering, terahertz spectroscopy, and molecular dynamics simulations.

The Landscape of m6A Regulators in Multiple Brain Regions of Alzheimer's Disease.

Alzheimer's disease research has been conducted for many years, yet no effective cure methods have been found. N6-methyladenosine (m6A) RNA methylation, an essential post-transcriptional regulation mechanism, has been discovered to affect essential neurobiological processes, such as brain cell development and aging, which are closely related to neurodegenerative diseases such as Alzheimer's disease. The relationship between Alzheimer's disease and the m6A mechanism still needs further investigation.

Facet-selective etching trajectories of individual semiconductor nanocrystals.

The size and shape of semiconductor nanocrystals govern their optical and electronic properties. Liquid cell transmission electron microscopy (LCTEM) is an emerging tool that can directly visualize nanoscale chemical transformations and therefore inform the precise synthesis of nanostructures with desired functions. However, it remains difficult to controllably investigate the reactions of semiconductor nanocrystals with LCTEM, because of the highly reactive environment formed by radiolysis of liquid.

Snapshots of a light-induced metastable hidden phase driven by the collapse of charge order.

Nonequilibrium hidden states provide a unique window into thermally inaccessible regimes of strong coupling between microscopic degrees of freedom in quantum materials. Understanding the origin of these states allows the exploration of far-from-equilibrium thermodynamics and the development of optoelectronic devices with on-demand photoresponses. However, mapping the ultrafast formation of a long-lived hidden phase remains a longstanding challenge since the initial state is not recovered rapidly.

High-speed two-dimensional terahertz spectroscopy with echelon-based shot-to-shot balanced detection.

By using a reflective-echelon-based electro-optic sampling technique and a fast detector, we develop a two-dimensional terahertz (THz) spectrometer capable of shot-to-shot balanced readout of THz waveforms at a full 1-kHz repetition rate. To demonstrate the capabilities of this new detection scheme for high-throughput applications, we use gas-phase acetonitrile as a model system to acquire two-dimensional THz rotational spectra. The results show a two-order-of-magnitude speedup in the acquisition of multidimensional THz spectra when compared to conventional delay-scan methods while maintaining accurate retrieval of the nonlinear THz signal.

The Protective A673T Mutation of Amyloid Precursor Protein (APP) in Alzheimer's Disease.

Alzheimer's disease is a progressive neurodegenerative disorder characterized by extracellular amyloid beta peptides and neurofibrillary tangles consisted of intracellular hyperphosphorylated Tau in the hippocampus and cerebral cortex. Most of the mutations in key genes that code for amyloid precursor protein can lead to significant accumulation of these peptides in the brain and cause Alzheimer's disease. Moreover, some point mutations in amyloid precursor protein can cause familial Alzheimer's disease, such as Swedish mutation (KM670/671NL) and A673V mutation.

Uncovering the Role of Hole Traps in Promoting Hole Transfer from Multiexcitonic Quantum Dots to Molecular Acceptors.

Understanding electronic dynamics in multiexcitonic quantum dots (QDs) is important for designing efficient systems useful in high power scenarios, such as solar concentrators and multielectron charge transfer. The multiple charge carriers within a QD can undergo undesired Auger recombination events, which rapidly annihilate carriers on picosecond time scales and generate heat from absorbed photons instead of useful work. Compared to the transfer of multiple electrons, the transfer of multiple holes has proven to be more difficult due to slower hole transfer rates.

Blockage of TGF- Induced by Spherical Silica Nanoparticles Inhibits Epithelial-Mesenchymal Transition and Proliferation of Human Lung Epithelial Cells.

. Xuanwei City in Yunnan province has been one of the towns with highest lung cancer mortality in China. The high content of amorphous silica in the bituminous coal from Xuanwei of Yunnan is mainly present as irregular and spherical silica nanoparticles (SiNPs).

Spherical silica nanoparticles promote malignant transformation of BEAS-2B cells by stromal cell-derived factor-1α (SDF-1α).

Objective: This study aimed to examine the role of spherical silica nanoparticles (SiNPs) on human bronchial epithelial (BEAS-2B) cells through inflammation.

Methods: Human mononuclear (THP-1) cells and BEAS-2B cells were co-cultured in transwell chambers and treated with 800 mmol/L benzo[ a]pyrene-7, 8-dihydrodiol-9, 10-epoxide (BPDE) and 12.5 µg/mL SiNPs for 24 hours.

AID expression is correlated with Bcr-Abl expression in CML-LBC and can be down-regulated by As2O3 and/or imatinib.

Activation-induced deaminase (AID), a cytidine deaminase, can accelerate the acquisition of BCR-ABL1 kinase domain mutations in human CML. In the present study, we investigated the expression of AID and Bcr-Abl in CML cells derived from 35 clinical patients. We found that both AID and Bcr-Abl were correlatively over-expressed in CML-LBC (lymphoid blast crisis) cells as compared with those in CML-CP (chronic phase) cells.

[Expression of human spindle mitosis arrest deficiency gene in spontaneous abortion embryo tissues].

Objective: To investigate the expression of human spindle mitosis arrest deficiency gene (hsMAD2) in spontaneous abortion embryos and the relationship between low expression of hsMAD2 and numerical chromosomal aberration. METHODS Spontaneous abortion embryo tissues were collected, including 23 cases of once spontaneous abortion tissue and 10 cases of twice or more spontaneous abortion tissue and induced abortion embryos (35 cases) from the Department of Gynaecology and Obstetrics of the Affiliated Hospitals of Chongqing University of Medical Science during the period of March 2006 to March 2007. FQ-PCR and western blot were used to evaluate the endogenous expression level of hsMAD2 mRNA and hsMAD2 protein; primary culturing of cells from the induced abortion embryos was conducted and 5 embryonic cells were selected by chromosomes karyotype analysis.