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Abstract Dust events are concerning due to their potential to cause environmental pollution and health issues by carrying numerous particles from various regions. However, the risks of airborne bacteria from dust have not yet been thoroughly investigated. This study aimed to reveal the particle size distribution, antibiotic resistance, microbial community structure, and diversity of airborne bacteria by using culture methods, and assess the potential health risks by calculating the dose expectation $$(\overline{d })$$ ( d ¯ ) , daily short-term intake (STI), and Hazard Index (HI) during an extreme dust event in urban Beijing (China). Airborne bacteria were sampled before, during, and the day after a severe dust event in March 2021 in Beijing using the six-stage impactor. The major findings were as follows: (1) airborne bacterial concentration increased during the dust event, and inhalable bacteria account for 67.93%. The Hazard Index (HI) of cultivable and inhalable airborne bacteria in men, women, and children exposed to dust events was up to 1.42 and 1.54 times higher than that in individuals who were not exposed, respectively. HI was 1.52 times higher in children than in men when exposed to the dust event. (2) The percentage of Gram-positive bacteria (GPB) resistant to different antibiotics was altered. The abundance of ciprofloxacin-resistant bacteria increased by 24.51%, while that of clindamycin-resistant bacteria decreased by 34.64%. The $$\overline{d }$$ d ¯ , STI, and HI of antibiotic-resistant bacteria per breath for men, women, and children after the dust event were 14 times greater than those before the dust event. (3) The diversity of airborne bacteria increased throughout the dust event. Opportunistic bacteria were found after the dust event. From a health perspective, airborne bacteria during extreme dust events should be further studied for their sources, changes, human exposure, and so forth. Government-scale measures are necessary to control dust dissemination. Graphical Abstract

Abstract The nucleus accumbens (NAc) is considered a hub of reward processing and a growing body of evidence has suggested its crucial role in the pathophysiology of major depressive disorder (MDD). However, inconsistent results have been reported by studies on reward network-focused resting-state functional MRI (rs-fMRI). In this study, we examined functional alterations of the NAc-based reward circuits in patients with MDD via meta- and mega-analysis. First, we performed a coordinated-based meta-analysis with a new SDM-PSI method for all up-to-date rs-fMRI studies that focused on the reward circuits of patients with MDD. Then, we tested the meta-analysis results in the REST-meta-MDD database which provided anonymous rs-fMRI data from 186 recurrent MDDs and 465 healthy controls. Decreased functional connectivity (FC) within the reward system in patients with recurrent MDD was the most robust finding in this study. We also found disrupted NAc FCs in the DMN in patients with recurrent MDD compared with healthy controls. Specifically, the combination of disrupted NAc FCs within the reward network could discriminate patients with recurrent MDD from healthy controls with an optimal accuracy of 74.7%. This study confirmed the critical role of decreased FC in the reward network in the neuropathology of MDD. Disrupted inter-network connectivity between the reward network and DMN may also have contributed to the neural mechanisms of MDD. These abnormalities have potential to serve as brain-based biomarkers for individual diagnosis to differentiate patients with recurrent MDD from healthy controls.

Thermoplastic polymer fiber–thermoplastic polymer matrix composites (PPCs or PRFPs), often recognized as self‐reinforced or single polymer composites, are potential candidates for future advanced polymer composites because of various advantages (e.g., recyclability, formability, low‐cost, ultra‐lightweight, environmental friendliness, etc.). The manufacturability and mechanical behavior of these composites compared to conventional carbon‐/glass‐/aramid‐fiber‐reinforced polymers is of great interest to the composites community, but there are a limited number of studies in this area. To this end, this paper reviewed fabrication methods with different processing parameters and mechanical behavior of uni‐/multi‐directional thermoplastic PPCs featuring continuous thermoplastic polymer fibers from limited data in the literature. It was shown that most specific behaviors (normalized by density) of these materials in various loading conditions (e.g., quasi‐static tension/shear/flexure, tension‐tension fatigue, and out‐of‐plane impacting, etc.) are comparable to or better than glass‐/aramid‐fiber‐reinforced polymers. Particularly, the specific ductility in the foregoing conditions outperforms all the carbon‐/glass‐/aramid‐fiber‐reinforced polymers. Thermoplastic PPCs with remarkable performance can be achieved through several uncomplicated methods (e.g., film stacking, hot compaction, powder and solution impregnations, matrix infusion and injection molding, additive manufacturing, etc.), which have some similarities to the methods used for carbon‐/glass‐/aramid‐fiber‐reinforced polymers. Moreover, several opportunities and challenging problems of thermoplastic PPCs were summarized at the end of this review paper. Efficient solutions may require countless efforts in the composites community to further strengthen the performance and understanding of thermoplastic PPCs for wide applications in various engineering fields in the future. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article Acrylonitrile‐butadiene‐lignin thermoplastic rubber adhesive for enhanced metal‐to‐metal joining by Zeyang Yu et al., https://doi.org/10.1002/pc.28258. [ABSTRACT FROM AUTHOR]

This paper presents the experimental and analytical studies to investigate the effect of concentrated butt-joints on the flexural properties of laminated bamboo-timber flitch beam (BTFB, or bio-flitch beam). The experimental results reveal that the concentrated butt-joints significantly reduce the flexural strength of the BTFB. They also suggest that the failure mechanism of the BTFB with or without concentrated butt-joints are completely different but less evidence shows an obvious effect of the butt-joints on the modulus of elasticity in bending. In addition, laminated bamboo lumber with concentrated butt-joints is found to be unsuitable for structural applications. The analytical predictions are in close agreement with the experimental results that demonstrate the potentials of the proposed analytical model as a forensic investigation instrument to estimate the strength reduction of the structure, if the butt-jointed laminated bamboo was, unfortunately, used in construction. [ABSTRACT FROM AUTHOR]

Air platform is the key equipment that affects the victory or defeat of modern war. In the high antagonistic environment of the future air combat, the "hard kill" active defense system becomes the key factor improving the survivability of air platforms. In order to study the key problems on the construction of air platform active defense system, the development status and current situation of foreign active defense system and equipments of air platforms are analyzed. According to the characteristics and operational requirements of the air platform active defense system, which must have all-direction situation awareness and attack capability, and achieve high-precision guidance and head-on interception under the fast rendezvous conditions, the key technologies of the air platform active defense system, such as high precision early warning, detection and tracking technology, all-direction attack technology, counter-parallel interception and guidance technology, interception and damage technology, and lightweight defense missile technology, are compared and analyzed. These studies can provide technical support for the research on active defense system and weapon equipment of air platform.