In this paper, direct adaptive neural-network (NN) control is presented for a class of affine nonlinear systems in the strict-feedback form with unknown nonlinearities. By utilizing a special property of the affine term, the developed scheme,avoids the controller singularity problem completely. All the signals in the closed loop are guaranteed to be semiglobally uniformly ultimately bounded and the output of the system is proven to converge to a small neighborhood of the desired trajectory. The control performance of the closed-loop system is guaranteed by suitably choosing the design parameters. Simulation results are presented to show the effectiveness of the approach.

Marine oil spills have induced severe water pollution and threatened sea ecosystems, which also result in a loss of energy resources. To deal with this problem, much work has been done for using superhydrophobic or superhydrophilic mesh for oil-water separation. Nevertheless, there are still great challenges in the rapid fabrication of extremely durable mesh with superwetting properties, particularly considering the highly efficient oil-water separation. In this study, we present a simple, efficient method to fabricate superhydrophilic and underwater superoleophobic stainless steel mesh surfaces with one-step femtosecond laser induced periodic nanoripple structures. The as-prepared mesh shows high separation efficiency, which is higher than 99% for various oil-water mixtures. More importantly, the wettability and the separation efficiency of the fabricated mesh show no obvious change after the abrasion tests and corrosion tests, indicating that the as-prepared samples possess robust stability. This study provides an efficient route for constructing durable and highly efficient separation mesh, which can be applied in the cleanup of large-scale oil spills in the near future.

Objective Up to 62% of perimenopausal women have depression symptoms. However, there is no efficacy treatment. The aim of this study is to compare the clinical efficacy and safety of EA therapy and escitalopram on perimenopause women with mild-moderate depressive symptom. Method A multicenter, randomized, positive-controlled clinical trial was conducted at 6 hospitals in China. 242 perimenopause women with mild-moderate depressive symptom were recruited and randomly assigned to receive 36 sessions of EA treatment or escitalopram treatment. The primary outcome measure was the 17-item Hamilton Depression Rating Scale (HAMD-17). The secondary outcome measures include menopause-specific quality of life (MENQOL) and serum sexual hormones which include estrogen, follicle-stimulating hormone, and luteinizing hormone. Results 221 (91.3%) completed the study, including 116 in the EA group and 105 in the escitalopram group. The baseline levels of demographic and outcome measurements were similar in the two groups. In the intervention period, there was no difference between two groups. However, in the follow-up, both HAMD-17 and MENQOL were significantly decreased, and at week 24 the mean differences were −2.23 and −8.97, respectively. There were no significant differences in the change of serum sexual hormones between the two groups. No serious adverse events occurred. Conclusion EA treatment is effective and safe in relieving depression symptom and improving the quality of life in the perimenopausal depression. Further research is needed to understand long-term efficacy and explore the mechanism of this intervention. This study is registered with ClinicalTrials.gov NCT02423694.

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We fabricated a superamphiphobic miniature boat with marked drag reduction and excellent loading capacity using femtosecond laser direct writing technology. The as-prepared superamphiphobic surface of the boat exhibited apparent contact angles larger than 150° toward both water and oil. Miniature boats with the superamphiphobic surface slid effortlessly on both water and oil-polluted water surfaces, with an increase in sliding distance by up to 52% and load increase of up to 27% compared with those of a boat with an untreated surface. A potential mechanism that explains the excellent performance of the superamphiphobic miniature boat was also discussed. This work provides a simple and economically viable strategy to obtain advanced surfaces for use in microfluidics and marine engineering.

This study presents a detailed fabrication method, together with validation, discussion, and analysis, for state-of-the-art silicon carbide (SiC) etching of vertical and bevelled structures by using inductively coupled plasma reactive ion etching (ICP-RIE) for microelectronic applications. Applying different gas mixtures, a maximum bevel angle of 87° (almost vertical), large-angle bevels ranging from 40° to 80°, and small-angel bevels ranging from 7° to 17° were achieved separately using distinct gas mixtures at different ratios. We found that SF6 with additive O2 was effective for vertical etching, with a best etching rate of 3050 Å/min. As for the large-angle bevel structures, BCl3 + N2 gas mixtures show better characteristics, exhibiting a controllable and large etching angle range from 40° to 80° through the adjustment of the mixture ratio. Additionally, a Cl2 + O2 mixture at different ratios is applied to achieve a small-angel bevels ranging from 7° to 17°. A minimum bevel angel of approximately 7° was achieved under the specific volume of 2.4 sccm Cl2 and 3.6 sccm O2. These results can be used to improve performance in various microelectronic applications including MMIC via holes, PIN diodes, Schottky diodes, JFETs’ bevel mesa, and avalanche photodiode fabrication.

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