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An accurate readout of the mechanical motion using optomechanical coupling is highly desired for on-chip sensing applications but it remains challenging due to the uncertainty caused by time-dependent parameters and noisy fluctuations. Here, we propose an efficient scheme to realize simultaneous measurement for both amplitude and frequency of the time-harmonic force (THF) in a hybrid optomechanical system via a nonlinear sum sideband effect. In this optomechanical system assisted by a degenerate parametric amplifier (DPA), the nonlinear optomechanical interaction between the external THF, optical, and mechanical modes is used to construct the frequency component of optical sum sidebands. Using experimentally achievable parameters, we find that the conversion efficiency of the sum sidebands has a significant enhancement when the nonlinear gain coefficient of DPA increases. In the scheme of the dual-parameter measurement, we also report that the amplitude of THF could be independently detected by observing the intensity variation of the lower sum sideband, while the frequency of THF could be separately read by monitoring the frequency of the prominent peak in this nonlinear spectrum. Benefitting from the optical cooling of a mechanical element, the theoretical results show that the minimum resolutions for detecting the amplitude and the frequency of THF are approximately 8.8 × 10 − 12 N and 16 Hz , respectively. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) from pathogenic bacterial biofilms has become a global health issue while developing novel antimicrobials is inefficient and costly. Combining existing multiple drugs with enhanced efficacy and/or reduced toxicity may be a promising approach to treat AMR. D‐amino acids mixtures coupled with antibiotics can provide new therapies for drug‐resistance infection with reduced toxicity by lower drug dosage requirements. However, iterative trial‐and‐error experiments are not tenable to prioritize credible drug formulations, owing to the extremely large number of possible combinations. Herein, a new avenue is provide to accelerate the exploration of desirable antimicrobial formulations via high‐throughput screening and machine learning optimization. Such an intelligent method can navigate the large search space and rapidly identify the D‐amino acid mixtures with the highest anti‐biofilm efficiency and also the synergisms between D‐amino acid mixtures and antibiotics. The optimized drug cocktails exhibit high antimicrobial efficacy while remaining non‐toxic, which is demonstrated not only from in vitro assessments but also the first in vivo study using a lung infection mouse model. [ABSTRACT FROM AUTHOR]

The sign of quantum interference (constructive or destructive) based on cavity optomechanics is crucial for observing quantum phenomena and designing high-sensitivity sensors with an integrable structure. Here, we propose an efficient scheme to generate constructive interference and optomechanically induced absorption (OMIA) in a hybrid atom–cavity optomechanical system. Using experimentally achievable parameters, we theoretically demonstrate that a gain-type OMIA dip with the extremely narrow linewidth and the enhanced spectral intensity can be modulated by an assisted atom that is excited by an external control field. More importantly, we report that a precise mass sensor is achieved by employing an observable correlation between the OMIA dip and the added mass deposited on the mechanical object. With the help of the back-action cooling of the mechanical object, we identify that the detection sensitivity and minimum resolution of the mass sensor can reach 3.14 MHz / ng and 1 fg , respectively. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing interest in the hyperspectral image (HSI) classification methods that employ deep learning techniques in small sample cases. To address issues with network degradation and enhance the extraction of discriminative HSI features, this article proposes a TBTA-D2Net network utilizing a triple-branch ternary-attention mechanism and Dense2Net. Furthermore, a new deep model optimizer named Adan is introduced to improve the training speed of the network model. This article takes spatial information as a two-dimensional vector, extracting spectral features as well as spatial-X and spatial-Y features separately in three branches. Each branch includes a Dense2Net bottleneck module and an attention module. Classification is achieved by fusing the features extracted from the three branches. Experimental results on four public datasets indicate that TBTA-D2Net can achieve competitive results over state-of-the-art methods. The code is available at . [ABSTRACT FROM AUTHOR]

In order to improve the wear resistance of medium-carbon steel, a dense WC-10Co-4Cr coating was prepared by high-velocity oxygen fuel (HVOF) spraying. The results show that the thickness of WC-10Co-4Cr coating is about 200 μm, which is mainly composed of WC, W2C, Co, Cr and Co6W6C phases, and its hardness is about 4.4 times higher than that of medium-carbon steel. The impact wear behavior of medium-carbon steel and WC-10Co-4Cr coating under ball-on-flat contact mode was systematically studied by using Si3N4 ball as impact pair. The results show that the deposition of WC-10Co-4Cr coating can significantly reduce the plastic damage and oxidation of the worn surface, thus inhibiting the initiation, propagation and connection of microcracks, as well as the crushing and spalling of surface materials. When the initial kinetic energy reaches 1.84 mJ, the width and depth of wear trace, wear volume and wear rate of WC-10Co-4Cr coating are about 96.01, 4.51, 4.17 and 4.98% of those of medium-carbon steel, respectively. In addition, the dominant wear mechanism of medium-carbon steel is plastic deformation, fatigue wear and oxidation, while the main wear mechanism of WC-10Co-4Cr coating is delamination and slight oxidation. [ABSTRACT FROM AUTHOR]