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To further investigate the role of vibration isolation structure in torpedo noise control, in this paper, a dynamic characteristic identification bench of vibration isolation materials based on a beam model was established, and the elastic modulus and damping of poly-ether-ether-ketone materials were identified and verified. The finite element model of bolt vibration isolation structure was established, and the accuracy of the model was verified. The model was applied to the connection between the torpedo engine and the shell. Combined with the vibration isolation ring modeling theory and bolt vibration isolation structure, a torpedo-powered vibration isolation simulation model was established for the first time. The simulation results show that the vibration noise of torpedoes can be reduced by 3.64 dB by comprehensively using vibration isolation rings combined with bolt connections. The results provide strong theoretical support for torpedo vibration noise control.

Abstract Ga‐doped zinc oxide (ZnO) microwires hold great promise for developing highly efficient light sources because of the wide bandgap with proper exciton binding energy. However, most microwires grown from one mainstream approach, i.e., chemical vapor deposition (CVD), are morphologically and crystallographically defective, exhibiting limited photoluminescence performances. Herein, a simple and effective X‐ray irradiation strategy is demonstrated for enhancing the photoluminescence of Ga‐doped ZnO microwire in ambient conditions. Under moderate doses (≤ 150 Gy), the photoluminescence monotonically rockets up with X‐ray dose increment and achieves nine‐fold enhancement at a dose of ≈150 Gy, recording high photoluminescence improvement of ZnO microwires to date. The elemental characteristics under different controlled irradiation atmospheres suggest the elimination of surface oxygen vacancy and the cross‐section transmission electron microscope reveals prominent lattice relaxations after mild X‐ray irradiation. In addition, the X‐ray irradiated microwires further exhibit elevated electroluminescence by over three times. The enhanced photoluminescence and electroluminescence as well as long‐term stability enable us to imagine the super‐rapid applications of ZnO microwires in modern optoelectronic devices.

Abstract Two-dimensional metal-organic frameworks (MOFs) have a wide variety of applications in molecular separation and other emerging technologies, including atomically thin electronics. However, due to the inherent fragility and strong interlayer interactions, high-quality MOF crystals of atomic thickness, especially isolated MOF crystal monolayers, have not been easy to prepare. Here, we report the self-condensation-assisted chemical vapour deposition growth of atomically thin MOF single-crystals, yielding monolayer single-crystals of poly[Fe(benzimidazole)2] up to 62 μm in grain sizes. By using transmission electron microscopy and high-resolution atomic force microscopy, high crystallinity and atomic-scale single-crystal structure are verified in the atomically MOF flakes. Moreover, integrating such MOFs with MoS2 to construct ultrathin van der Waals heterostructures is achieved by direct growth of atomically MOF single-crystals onto monolayer MoS2, and enables a highly selective ammonia sensing. These demonstrations signify the great potential of the method in facilitating the development of the fabrication and application of atomically thin MOF crystals.

Abstract We hypothesized that the combined use of etomidate and propofol for endoscopic sedation in elderly hypertensive patients could reduce adverse reactions while providing ideal sedation. To validate our hypothesis, we conducted a prospective, randomized, controlled, double‐blinded study. A total of 360 elderly hypertensive patients scheduled for gastroscopy at our hospital were enrolled in the study, of whom 328 completed the trial. The patients were randomly assigned to one of three groups: the propofol group (group P), the etomidate group (group E), or the propofol‐etomidate combination group (mixed at a ratio of 1:1, group PE). We collected and analyzed the cardiopulmonary effects and side effects in each group. Regardless of the sedation drug used, the systolic blood pressure, mean blood pressure, and heart rate of involved patients were significantly affected. Oxygen desaturation and injection pain were more common in group P compared to groups E (33.6% vs. 14.8%, 31.8% vs. 2.7%, both P

Low-dimensional materials (LDMs), due to exotic mechanical, optical and electrical properties enhanced by ultrahigh surface-to-volume ratio and quantum confinements, have taken centerstage in nanoelectromechanical system (NEMS) resonators. The ability to survive from high strains and complex environments enables LDMs-based NEMS resonators innovative effectuations for mass-, gas- and bio-sensings and computings. In this review, we highlighted the fabrication, actuation, detection, figure of merit, influence factors and recent process of LDMs-based NEMS resonators. After overviewing representative applications and feasible directions, we summarized the confronted challenges in fabrications, tunings and utilizations of LDMs-based NEMS resonators. Finally, the prospects that may properly tackle these obstacles were concluded, attempting to offer useful guidelines for both theoretical and experimental experts to promote NEMS resonators one step closer toward industrializations.

BackgroundOverweight/obesity in children are a global health issue. Preschool age is an important stage of children's growth and development and dietary behaviors, so it is crucial to explore dietary behavior characteristics and childhood overweight/obesity.ObjectiveTo explore the association between dietary behavior characteristics and overweight/obesity in preschool children in Shanghai, and the consistency of children's eating behavior characteristics with their parents'.MethodsThe children aged 3 to 6 years in 5 kindergartens in Shanghai in 2015 were selected by convenience sampling and surveyed. Their height and weight were measured. Children's and parents' dietary behavior characteristics were self-reported by their parents. According to the weight-for-height recommended by the World Health Organization, excess weight was calculated by the following formula: excess-weight%=[(measured weight - standard weight)/standard weight×100%]; obese is determined at excess-weight% > 20%, overweight: excess-weight% at 10%-20%, normal weight: excess-weight% at −10%-

Abstract 2D materials (2DMs), due to spin‐valley locking degree of freedom, exhibit strongly bound exciton and chiral optical selection rules and become promising material candidates for optoelectronic and spin/valleytronic devices. Over the last decade, the manifesting of 2D materials by circularly polarized lights expedites tremendous fascinating phenomena, such as valley/exciton Hall effect, Moiré exciton, optical Stark effect, circular dichroism, circularly polarized photoluminescence, and spintronic property. In this review, recent advance in the interaction of circularly polarized light with 2D materials covering from graphene, black phosphorous, transition metal dichalcogenides, van der Waals heterostructures as well as small proportion of quasi‐2D perovskites and topological materials, is overviewed. The confronted challenges and theoretical and experimental opportunities are also discussed, attempting to accelerate the prosperity of chiral light‐2DMs interactions.

The toxicity arising from generalised stimulation of T cells restricts applicability of CD137 agonists in cancer immune therapy. Here authors show that a bispecific antibody blocking PD-1 while activating CD137 efficiently restricts T cell activation to the tumour microenvironment, resulting in efficient tumour control and reduced liver toxicity.

Common photovoltaic effect is across the interface of heterojunctions. Here, the authors find that scanning a light beam can induce a persistent in-plane photoelectric voltage along silicon-water interfaces, due to the following movement of a charge packet in the vicinity of the silicon surface.

Rigidity, as seen in crosslinked polymers, and plastic processability are mutually exclusive properties. Here, the authors prepare a solution-processable conjugated microporous thermoset with permanent pores and demonstrate its application as a two-dimensional molecular sieving membrane for hydrogen separation.

Abstract Single‐metal‐atom catalysts (SMACs) with the merits of maximum atom utilization, peculiar electronic structure, and adjustable coordination environment, have emerged as the rising stars. They are not only regarded as the promising electrocatalysts, but also show unconventionally excellent alkali storage, thus enabling them for energy devices. In this work, we review the up‐to‐date progress of single metal atom catalysts including the detailed synthetic strategies and all sorts of applications in energy storage and conversion. In addition, we also discuss intrinsic catalytic effects, degradation mechanism, modulation approaches, support structure design, current challenges, and potential development trends. This work may shed light on developing high‐performance SMACs using a variety of strategies for catalytic and energy applications.

The poor bioavailability of curcumin and its derivatives limits their antitumor efficacy and clinical translation. Although curcumin derivative C210 has more potent antitumor activity than curcumin, it has a similar deficiency to curcumin. In order to improve its bioavailability and accordingly enhance its antitumor activity in vivo, we developed a redox-responsive lipidic prodrug nano-delivery system of C210. Briefly, we synthesized three conjugates of C210 and oleyl alcohol (OA) via different linkages containing single sulfur/disulfide/carbon bonds and prepared their nanoparticles using a nanoprecipitation method. The prodrugs required only a very small amount of DSPE-PEG2000 as a stabilizer to self-assemble in aqueous solution to form nanoparticles (NPs) with a high drug loading capacity (~50%). Among them, the prodrug (single sulfur bond) nanoparticles (C210-S-OA NPs) were the most sensitive to the intracellular redox level of cancer cells; therefore, they could rapidly release C210 in cancer cells and thus had the strongest cytotoxicity to cancer cells. Furthermore, C210-S-OA NPs exerted a dramatic improvement in its pharmacokinetic behavior; that is, the area under the curve (AUC), mean retention time and accumulation in tumor tissue were 10, 7 and 3 folds that of free C210, respectively. Thus, C210-S-OA NPs exhibited the strongest antitumor activity in vivo than C210 or other prodrug NPs in mouse models of breast cancer and liver cancer. The results demonstrated that the novel prodrug self-assembled redox-responsive nano-delivery platform was able to improve the bioavailability and antitumor activity of curcumin derivative C210, which provides a basis for further clinical applications of curcumin and its derivatives.

Abstract The interlayer modification and the intercalation pseudocapacitance have been combined in vanadium oxide electrode for aqueous zinc‐ion batteries. Intercalation pseudocapacitive hydrated vanadium oxide Mn1.4V10O24·12H2O with defective crystal structure, interlayer water, and large interlayer distance has been prepared by a spontaneous chemical synthesis method. The inserted Mn2+ forms coordination bonds with the oxygen of the host material and strengthens the interaction between the layers, preventing damage to the structure. Combined with the experimental data and DFT calculation, it is found that Mn2+ refines the structure stability, adjusts the electronic structure, and improves the conductivity of hydrated vanadium oxide. Also, Mn2+ changes the migration path of Zn2+, reduces the migration barrier, and improves the rate performance. Therefore, Mn2+‐inserted hydrated vanadium oxide electrode delivers a high specific capacity of 456 mAh g−1 at 0.2 A g–1, 173 mAh g–1 at 40 A g–1, and a capacity retention of 80% over 5000 cycles at 10 A g–1. Furthermore, based on the calculated zinc ion mobility coefficient and Zn(H2O)n2+ diffusion energy barrier, the possible migration behavior of Zn(H2O)n2+ in vanadium oxide electrode has also been speculated, which will provide a new reference for understanding the migration behavior of hydrated zinc‐ion.

A simple, rapid, and sensitive liquid chromatography (LC)/mass spectrometry (MS) method was established and validated for simultaneous quantitation of pyrazinamide, isoniazid, rifampicin, and ethambutol in human blood sample. Samples were pretreated by a single-step precipitation with acetonitrile. Chromatographic separation was achieved on XSelecT HSS T3 column by gradient elution with a total run time of 5.0 min. MS detection was performed by a triple quadrupole tandem mass spectrometer in the multiple reaction monitoring mode with a positive electrospray ionization source. Isotope-labeled internal standard, especially rifampicin-D8, was applied to adjust for the loss during sample treatment. The established LC-MS/MS method showed a wide analytical range (pyrazinamide: 1.02∼60.0 μg/mL, isoniazid: 0.152∼10.0 μg/mL, rifampicin: 0.500∼30.0 μg/mL, and ethambutol: 0.0998∼5.99 μg/mL) and a good linearity (r > 0.99 for the four analytes) with acceptable accuracy and precision (90.15%∼104.62% and 94.00%∼104.02% for intra- and interaccuracy, respectively; RSD%:

Laser drive ramp compression is an important method to achieve an extremely high-pressure but relatively low-temperature material state. In this study, we found VISAR streaks disappearing under high pressure. To solve this problem, the mechanism of probe-laser absorption in laser drive ramp compression experiments has been studied, and X-ray preheat is found to be the main factor in this mechanism. Subsequently, target configuration optimization and code simulation were performed based on previous experiments, and laser drive ramp compression experiments were performed on the SHENGGUANG prototype facility. In the experiments, the probe-laser reflectivity was above 90% at 450 GPa, which is much higher than those in previous experiments, demonstrating that the X-ray preheat was shielded well with the optimized target configuration.

In the pattern recognition domain, deep architectures are currently widely used and they have achieved fine results. However, these deep architectures make particular demands, especially in terms of their requirement for big datasets and GPU. Aiming to gain better results without deep networks, we propose a simplified algorithm framework using fusion features extracted from the salient areas of faces. Furthermore, the proposed algorithm has achieved a better result than some deep architectures. For extracting more effective features, this paper firstly defines the salient areas on the faces. This paper normalizes the salient areas of the same location in the faces to the same size; therefore, it can extracts more similar features from different subjects. LBP and HOG features are extracted from the salient areas, fusion features’ dimensions are reduced by Principal Component Analysis (PCA) and we apply several classifiers to classify the six basic expressions at once. This paper proposes a salient areas definitude method which uses peak expressions frames compared with neutral faces. This paper also proposes and applies the idea of normalizing the salient areas to align the specific areas which express the different expressions. As a result, the salient areas found from different subjects are the same size. In addition, the gamma correction method is firstly applied on LBP features in our algorithm framework which improves our recognition rates significantly. By applying this algorithm framework, our research has gained state-of-the-art performances on CK+ database and JAFFE database.