Spontaneous breaking and re-making of the RS-Au-SR staple in self-assembled ethylthiolate/Au(111) interface

The stability of the self-assembled RS–Au–SR (R = CH₂CH₃)/Au­(111) interface at room temperature has been investigated using scanning tunneling microscopy (STM) in conjunction with density functional theory (DFT) and MD calculations. The RS–Au–SR staple, also known as Au-adatom-dithiolate, assembles into staple rows along the [112̅] direction. STM imaging reveals that while the staple rows are able to maintain a static global structure, individual staples within the row are subjected to constant breaking and remaking of the Au–SR bond. The C₂S–Au–SC₂/Au­(111) interface is under a dynamic equilibrium and it is far from rigid. DFT/MD calculations show that a transient RS–Au–Au–SR complex can be formed when a free Au atom is added to the RS–Au–SR staple. The relatively high reactivity of the RS–Au–SR staple at room temperature could explain the reactivity of thiolate-protected Au nanoclusters, such as their ability to participate in ligand exchange and intercluster reactions

B Cell-Related Circulating MicroRNAs With the Potential Value of Biomarkers in the Differential Diagnosis, and Distinguishment Between the Disease Activity and Lupus Nephritis for Systemic Lupus Erythematosus

Our understanding of circulating microRNAs (miRNAs) related to systemic lupus erythematosus (SLE) remains very limited. In this study, we screened SLE-specific miRNAs in plasma from 42 B cell-related miRNAs by using miRNA PCR Array. The selected miRNAs were first confirmed in plasma samples from 50 SLE patients, 16 rheumatoid arthritis (RA) patients, and 20 healthy donors using qRT-PCR. We then investigated the relationship between expressions of the selected miRNAs and SLE clinical indicators. As a result, 14 miRNAs (miR-103, miR-150, miR-20a, miR-223, miR-27a, miR-15b, miR-16, miR-181a, miR-19b, miR-22, miR-23a, miR-25, miR-92a, and miR-93) were significantly decreased in the plasma of SLE patients compared with healthy controls (P < 0.05) and could act as the diagnostic signature to distinguish SLE patients from healthy donors. Six miRNAs (miR-92a, miR-27a, miR-19b, miR-23a, miR-223, and miR-16) expressed in plasma were significantly lower in SLE patients than in RA patients (P < 0.05), revealing the potentially diagnostic signature to distinguish SLE patients from RA patients. Furthermore, the downregulated expression of miR-19b, miR-25, miR-93, and miR-15b was associated with SLE disease activity (P < 0.05) while miR-15b and miR-22 expressions were significantly lower in SLE patients with low estimate glomerular filtration rate (eGFR < 60 ml/min/1.73 m2) (P < 0.05). The diagnostic potential of miR-15b for SLE disease activity and lupus nephritis (LN) with low eGFR was validated on an independent validation set with 69 SLE patients and a cross-validation set with 80 SLE patients. In summary, the signature of circulating miRNAs will provide novel biomarkers for the diagnosis of SLE and evaluation of disease activity and LN

Temperature Drift Compensation of a MEMS Accelerometer Based on DLSTM and ISSA

In order to improve the performance of a micro-electro-mechanical system (MEMS) accelerometer, three algorithms for compensating its temperature drift are proposed in this paper, including deep long short-term memory recurrent neural network (DLSTM-RNN, short DLSTM), DLSTM based on sparrow search algorithm (SSA), and DLSTM based on improved SSA (ISSA). Moreover, the piecewise linear approximation (PLA) method is employed in this paper as a comparison to evaluate the impact of the proposed algorithm. First, a temperature experiment is performed to obtain the MEMS accelerometer’s temperature drift output (TDO). Then, we propose a real-time compensation model and a linear approximation model for neural network methods compensation and PLA method compensation, respectively. The real-time compensation model is a recursive method based on the TDO at the last moment. The linear approximation model considers the MEMS accelerometer’s temperature and TDO as input and output, respectively. Next, the TDO is analyzed and optimized by the real-time compensation model and the three algorithms mentioned before. Moreover, the TDO is also compensated by the linear approximation model and PLA method as a comparison. The compensation results show that the three neural network methods and the PLA method effectively compensate for the temperature drift of the MEMS accelerometer, and the DLSTM + ISSA method achieves the best compensation effect. After compensation by DLSTM + ISSA, the three Allen variance coefficients of the MEMS accelerometer that bias instability, rate random walk, and rate ramp are improved from 5.43×10−4mg, 4.33×10−5mg/s12, 1.18×10−6mg/s to 2.77×10−5mg, 1.14×10−6mg/s12, 2.63×10−8mg/s, respectively, with an increase of 96.68% on average

Pd nanoparticle-decorated Bi4O5Br2 nanosheets with enhanced visible-light photocatalytic activity for degradation of Bisphenol A

Bismuth oxyhalides are important visible-light-responsive photocatalysts due to their unique electronic and layered crystal structure. In this study, Pd nanoparticles with the size of about 3-6 nm were loaded on the Bi4O5Br2 nanosheets by applying solvothermal-reduction method. The photoelectrochemical performance and photocatalytic activity for the degradation of Bisphenol A in aqueous solution of Bi4O5Br2 and Pd/Bi4O5Br2 were evaluated. Compared with pure Bi4O5Br2, Pd/Bi4O5Br2 exhibited an excellent photocatalytic activity for the degradation of Bisphenol A in aqueous solution under LED visible light irradiation. 1.0 wt% loading of Pd was found to be most effective for improving the photocatalytic activity of Bi4O5Br2 for the degradation of Bisphenol A and near to 95.8% of degradation was achieved after 70 min LED visible light irradiation. Under 535 and 630 nm monochromatic LED visible light irradiation for 70 min, only 7.9% and 4.8% Bisphenol A were degraded over 1.0% Pd/Bi4O5Br2 photocatalysts, respectively. Therefore, the improved photocatalytic activity of Pd/Bi4O5Br2 is mainly attributed to the formation of a Schottky barrier between the Pd nanoparticle and the Bi4O5Br2 nanosheet, promoting efficient separation of photogenerated electrons and holes. (C) 2018 Elsevier B.V. All rights reserved

One-step solvothermal synthesis of Fe-doped BiOI film with enhanced photocatalytic performance

Ultrathin nanosheets consisting of Fe-doped BiOI were obtained on a FTO (SnO2:F) glass substrate via a simple solvothermal process.</p