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Consumers are attracted to traditional fermented foods due to their unique flavor and nutritional value. However, the traditional fermentation technique can no longer accommodate the requirements of the food industry. Traditional fermented foods produce hazardous compounds, off‐odor, and anti‐nutritional factors, reducing product stability. The microbial system complexity of traditional fermented foods resulting from the open fermentation process has made it challenging to regulate these problems by modifying microbial behaviors. Synthetic microbial communities (SynComs) have been shown to simplify complex microbial communities and allow for the targeted design of microbial communities, which has been applied in processing traditional fermented foods. Herein, we describe the theoretical information of SynComs, particularly microbial physiological processes and their interactions. This paper discusses current approaches to creating SynComs, including designing, building, testing, and learning, with typical applications and fundamental techniques. Based on various traditional fermented food innovation demands, the potential and application of SynComs in enhancing the quality of traditional fermented foods are highlighted. SynComs showed superior performance in regulating the quality of traditional fermented foods using the interaction of core microorganisms to reduce the hazardous compounds of traditional fermented foods and improve flavor. Additionally, we presented the current status and future perspectives of SynComs for improving the quality of traditional fermented foods. [ABSTRACT FROM AUTHOR]

A floating foundation vibration reduction system with an air spring as a vibration isolation element has been widely used in the foundation of large ultra-precision instruments. With the excellent vibration isolation performance of the air spring, its complex dynamic nonlinear behavior is always a research difficulty. In this paper, a dynamic model of a floating foundation vibration reduction system based on the restoring force of air spring is derived. The structure of the recurrent convolution neural network (RCNN) is proposed based on combining the working characteristics of a convolution neural network and a long short-term memory neural network, and the dynamic model of a floating foundation vibration reduction system is established with the restoring force of the air spring calculated by the RCNN as the input. Finally, a test experiment was designed to compare the dynamic characteristics of the traditional numerical model and three deep neural network models in the floating foundation. The results show that convolution neural network, long short-term memory, and RCNN models could predict the vibration response of floating foundation vibration reduction system, and the RCNN model had better performance for a floating foundation.

Steel plate concrete composite (SPCC) structure plays an essential role in modular construction, which has been widely applied in the floating foundation vibration reduction system. This study proposed a basis for designing an SPCC floating foundation vibration reduction system with an air spring as the main vibration isolation element. Based on the engineering thermodynamics and aerodynamics theories, the non-linear state equations and dynamic equations of each component of the air spring with auxiliary chamber were established, respectively. According to the operational characteristics of the air spring, the equations were linearized by using the small deviation linearization method under the condition of small amplitude, and the linearized model of the dynamic stiffness of the air spring with an auxiliary chamber was therefore proposed. The reliability of the proposed method was proved by a floating foundation vibration test, which was performed in a solid-state quantum laboratory. The constitutive equations of an air spring model and an SPCC floating foundation model were incorporated into the STERA_3D software. The simulation results showed good agreement with the low-frequency micro-vibration region test data.

Understanding evolution of antibiotic resistance is vital for containing its global spread. Yet our ability to in situ track highly heterogeneous and dynamic evolution is very limited. Here, we present a new single‐cell approach integrating D2O‐labeled Raman spectroscopy, advanced multivariate analysis, and genotypic profiling to in situ track physiological evolution trajectory toward resistance. Physiological diversification of individual cells from isogenic population with cyclic ampicillin treatment is captured. Advanced multivariate analysis of spectral changes classifies all individual cells into four subsets of sensitive, intrinsic tolerant, evolved tolerant and resistant. Remarkably, their dynamic shifts with evolution are depicted and spectral markers of each state are identified. Genotypic analysis validates the phenotypic shift and provides insights into the underlying genetic basis. The new platform advances rapid phenotyping resistance evolution and guides evolution control. [ABSTRACT FROM AUTHOR]

The background noise (BGN) of test equipment affects the lower detection limit of the measurement range, and achieving an ultralow BGN is identified as a formidable challenge for highly accurate testing of a free-standing film. In this paper, a new gas transmission rate test apparatus is designed by detecting the electrical resistance increase with calcium corrosion. Thanks to the new design strategy, the only permeable place of this apparatus is the clamping and holding site. Mathematical methods for calculating the molecular permeation behaviors and magnitude of BGN are devised. The results show that the properties and structures of the materials significantly affect the BGN value. By using a sealant with low permeability (2.25 × 10−15 g cm cm−2 s−1 Pa−1) and a clamping ring with small width (2.5 mm) and testing an ultrahigh barrier (WVTR: 10−6 g m−2 day−1), the BGN could reach a level of 10−11 g m−2 day−1. With theoretical guidance, after optimization, one sealing structure obtained an ultralow BGN value (∼10−6 g m−2 day−1) in the actual test. The electrical resistance test has many advantages over existing methods. Additionally, the computational method devised in this study to examine the effects of materials provides a useful tool to achieve high-accuracy testing. [ABSTRACT FROM AUTHOR]

Polymers are ideal materials for preparing flexible barrier films because of their flexibility and other outstanding comprehensive properties. However, the gas barrier performance of polymer is far from meeting the requirements of flexible electronics encapsulation and its technology is still very challenging. In this study, by imitating the "brick‐mortar" structure of nacres, the nacre‐like composites made by polyimide (PI) and montmorillonites (MMTs) are successfully prepared by gravity‐induced deposition. These composite films exhibit excellent water vapor barrier performance even under high humidity conditions. The water vapor transmission rate of the best composite film (PNC50) is 0.023 g m−2 day−1, which is 3 orders of magnitude lower than that of pure PI. Mechanism studies are carried out by the help of carbon quantum dots, which could "lighting up" the MMTs and thus directly reflect the dispersion state of MMT in the composite films. With a fluorescence confocal microscopy, it can be observed that MMTs are evenly arranged on the surface, effectively blocking the entry of water vapor; moreover, the dense laminated structure of MMTs can prevent the diffusion of water vapor, all of which are beneficial to improve the water vapor barrier property of the composite films. [ABSTRACT FROM AUTHOR]

A good packing of flexible electronics is one of the most critical points to ensure its lifetime. However, efficient and straightforward packaging technology is still very challenging. In this work, a new strategy for preparing encapsulation film is reported by "enameling" a fusible glass layer on a polymer membrane. Careful consideration has been given to the materials properties and manufacturing process, and the obtained glass‐coated polymer can combine the advantageous properties of polymers and inorganic materials unconventionally. The encapsulation films show exceptional overall properties, including transparency (<5% optical deterioration), flexibility (radius of curvature: 1.5 mm), and low permeability. The film with 12 µm glass layer exhibits a water vapor transmission rate of 5.7 × 10−4 g m−2 day−1, and an oxygen transmission rate of 1.46 × 10−4 g m−2 day−1, which is 5 and 3 orders of magnitude lower than that of the polymer substrate, respectively. The fabrication process is suitable for roll‐to‐roll manufacturing, showing great advantages over the existing deposition methods like plasma‐enhanced chemical vapor deposition and atomic layer deposition in terms of reducing manufacturing costs and simplifying the process. Therefore, it is a significant contribution to the development of flexible electronics packaging technology. [ABSTRACT FROM AUTHOR]

In this paper, cold atmospheric pressure brush-shaped plasmas are reported. The brush, which is driven by a direct current (dc) power supply, is capable of generating plasmas glow up to 30-mm wide with no gas flow supplement. The plasmas can be touched by bare hand without any feeling of electrical shock or warmth. Current measurements show that the discharge in air appears periodically pulsed, while the discharge in argon actually presents either pulsed, except for their discharge mechanism placed at differently. For understanding this particular characteristic, a 2-D fluid model is developed with the use of Comsol Multiphysics software, under the condition of discharge in argon treated as an example. The simulation results are in good agreement with our discharge experiment in argon, which further indicate that the space charges trapped along the whole dielectric surface in air but only confined in the hole ahead the anode needle tip in argon may be responsible for the generation of the different pulsed discharges. [ABSTRACT FROM PUBLISHER]

In the above-named work, the affiliation of the first author is incorrect. It is corrected herein. [ABSTRACT FROM PUBLISHER]

The underground coal gasification (UCG) mining technology constitutes an innovative form of clean energy technology pertaining to coal resources. The sandstone specimens from the roof and floor of coal seam were collected and heat treated at 25 °C–800 °C in laboratory. According to the test results of physical parameters, 400 °C is the temperature turning point for the physical parameters such as mass, longitudinal P-wave velocity, porosity, and water absorption of sandstone specimens to change from "slow" to "drastic". The uniaxial compression test showed that the uniaxial compressive strength (UCS) of sandstone specimens decreases by 3.22% when the temperature rises from 25 °C to 200 °C, and by 5.70% when the temperature rises from 600 °C to 800 °C, both of which show temperature degradation effect. However, in the range of 200 °C–600 °C, the average UCS of sandstone specimens increases from 122.80 MPa to 162.54 MPa, showing obvious strength strengthening effect. In order to fully elucidate the mechanism of mechanical properties strengthening and degradation of tunnel surrounding rock under high temperature, X-ray diffraction (XRD), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were combined in the experiment. We concluded that these two intensity effects can be explained by physical and chemical reactions, including mineral composition thermal expansion, thermally induced microcrack and healing effects, phase transformation of the rock-forming mineral quartz, dehydration and thermal decomposition of mica, as well as dehydration and dehydroxylation of illite. The research results can provide theoretical basis for UCG roof and floor disaster prevention evaluation and tunnel support system design. • Rock performances evaluation of roof and floor for use in UCG applications. • The strength degradation and strengthening effects of high temperature sandstone have been discussed. • The physical and mechanical properties of sandstone are changed by temperature, and 400 °C is the threshold temperature. • The changes of physical mechanics of high temperature sandstone have been elucidated in macroscopic and microscopic aspects. • The thermal degradation and strengthening effects are caused by the physical and chemical reactions of rock-forming minerals. [ABSTRACT FROM AUTHOR]