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Crayfish (Procambarus clarkii) is nutritious and delicious, but its safety always worries consumers. This study aimed to investigate the microbial safety of frozen cooked crayfish. The total volatile basic nitrogen (TVB-N) content and pH of crayfish samples were measured to determine the end point of the shelf life. The structure and diversity of the microbial communities in the viscera and gills, muscle and shell of crayfish and the marinade were analyzed by high-throughput sequencing. The results showed that during the frozen storage of cooked crayfish, the pH of the viscera, gills and muscle decreased slowly, while the pH of the marinade and the shell increased first and then decreased. The TVB-N contents of all four samples showed an upward trend. On the 180th day, the TVB-N values of the muscle as well as the viscera and gills were 32.42 and 31.26 mg/100 g, respectively, which were higher than the accepted upper limit. The results of high-throughput sequencing showed that there were differences in the bacterial community structure of the four crayfish samples at the end of the shelf life. The decreasing order of the abundance of bacteria in these samples were marinade > viscera and gills > shell > muscle. The dominant bacterial genera in these samples were also different; Lactobacillus was dominant in the marinade. Psychrobacter and Vibrio were dominant in the viscera and gills, the dominant bacteria in the shell were Vibrio, Lactobacillus and Psychrobacter, and the dominant bacteria in the muscle were Psychrobacter and Acinetobacter. In conclusion, the microbial safety risk of the marinade and the viscera and gills in frozen cooked crayfish products was relatively high and could be reduced by combined use of various cleaning methods, adjusting the acidity of the marinade and using antibacterial agents.

Culver City is anticipating a surge in economic growth in upcoming years, attributed to an influx of large employers. Its challenge will be in meeting growth objectives while managing increasing traffic congestion and emissions – a tall order on any given day, but especially so in light of the ongoing coronavirus pandemic. Culver City faces additional headwinds in counteracting potentially long-term, destructive changes to travel behavior, and operating under constrained city budgets during these times of austerity. This report focuses on three promising, cost-effective, and infrastructure-light strategies local officials can consider to advance their vision of a more walkable, bikeable, sustainable, and livable Culver City with improved circulation; they are: formation of a local transportation management association, transforming parking management, and consideration of various road pricing schemes. An analysis of local employment patterns, regulations, and traffic conditions informs our context-specific recommendations for their implementation in Culver City.

In this work, we report a counter-intuitive activation of abnormal grain growth (AGG) in randomly-oriented fine grains (FGs) in an L-PBF Al–Mg–Sc–Zr alloy, which is unlikely from perspectives of curvature-driven grain growth, crystallographic texture or strain-induced boundary migration. The observed spontaneous AGG is understood in light of the growth instability of an arbitrary grain in an evolving particle-pinned polycrystalline aggregation. A generalized criterion for AGG is hence proposed, which efficaciously explains the observed susceptibility of FGs to AGG, the presence of multiple AGG activation sites, and the asynchrony of AGG activation. [ABSTRACT FROM AUTHOR]

Motivations, including intrinsic and extrinsic motivations, are impactful factors that contribute to the development of math anxiety or increasing math anxiety level of learners at different ages. Considering the importance of mathematics for the population in the society today and the fact that math learning is not enjoyable for everyone, reviewing and comparing the effects of different types of extrinsic motivation on varied age groups of learners’ math anxiety level is necessary. Specifically, the present paper compared the influences of external regulation, introjected regulation, and identification on elementary age learners’ math anxiety level and adolescent learners’ math anxiety level, and found three major differences among the influences of the three types of extrinsic motivations between the two age groups: first, external regulation from authority figures has more negative effects in math anxiety of elementary age learners; second, external regulation from peers and society are more influential factors causing the alteration of the adolescent learners’ math anxiety level; third, identification-led math anxiety aggravates as pressure of math learning increases. It aims to provide assistance to the teachers and caregivers of the learners on promoting the learners to make use of their full potential in math learning, and also, aims to provide reference for future studies in relevant fields. It is expected that future studies would conduct relevant researches more creatively and look into specific areas in the field (for example, identification in different levels of learners and introjected regulation in learners) in order to dig deeper into the field.

Although astrocytes are the most abundant cell type in the central nervous system (CNS), little is known about their molecular specification and differentiation. It has previously been reported that transcription factor Nkx6.1 is expressed in neuroepithelial cells that give rise to astrocyte precursors in the ventral spinal cord. In the present study, we systematically investigated the function of Nkx6.1 in astrocyte development using both conventional and conditional Nkx6.1 mutant mice. At early postnatal stages, Nkx6.1 was expressed in a subpopulation of astrocytes in the ventral spinal cord. In the conventional Nkx6.1KO spinal cord, the initial specification of astrocyte progenitors was affected by the mutation, and subsequent migration and differentiation were disrupted in newborn mice. In addition, the development of VA2 subtype astrocytes was also inhibited in the white matter. Further studies with Nkx6.1 conditional mutants revealed significantly delayed differentiation and disorganized arrangement of fibrous astrocytes in the ventral white matter. Together, our studies indicate that Nkx6.1 plays a vital role in astrocyte specification and differentiation in the ventral spinal cord.

In the context of mountain tunnel mining through the drilling and blasting method, the recognition of lithology from palm face images is crucial for the comprehensive analysis of geological conditions and the prevention of geological risks. However, the complexity of the background in the acquired palm face images, coupled with an insufficient data sample size, poses challenges. While the incorporation of deep learning technology has enhanced lithology recognition accuracy, issues persist, including inadequate feature extraction and suboptimal recognition accuracy. To address these challenges, this paper proposes a lithology recognition network integrating attention mechanisms and a feature Brownian distance covariance approach. Drawing inspiration from the Brownian distance covariance concept, a feature Brownian distance covariance module is devised to enhance the network's attention to rock sample features and improve classification accuracy. Furthermore, an enhanced lightweight Convolutional Block Attention Module is introduced, with upgrades to the multilayer perceptron in the channel attention module. These improvements emphasize attention to lithological features while mitigating interference from background information. The proposed method is evaluated on a palm face image dataset collected in the field. The proposed method was evaluated on a dataset comprising field-collected images of a tunnel rock face. The results illustrate a significant enhancement in the improved model's ability to recognize rock images, as evidenced by improvements across all objective evaluation metrics. The achieved accuracy rate of 97.60% surpasses that of the current mainstream lithology recognition neural network. [ABSTRACT FROM AUTHOR]

Producing oxygen and hydrogen via the electrolysis of water has the advantages of a simple operation, high efficiency, and environmental friendliness, making it the most promising hydrogen production method. In this study, La0.2Sr0.8Cu0.4Co0.6O3−δ (LSCC) nanofibers were prepared by electrospinning to utilize non-noble perovskite oxides instead of noble metal catalysts for the oxygen evolution reaction, and the performance and electrochemical properties of LSCC nanofibers synthesized at different firing temperatures were evaluated. In an alkaline environment (pH = 14, 6 M KOH), the nanofibers calcined at 650 °C showed an overpotential of 209 mV at a current density of 10 mA cm−2 as well as good long-term stability. Therefore, the prepared LSCC-650 NF catalyst shows excellent potential for electrocatalytic oxygen evolution. [ABSTRACT FROM AUTHOR]

In view of the importance of environmental accounting to ecological governance, this article attempts to study the economic consequences of environmental information disclosure quality (EID) from the perspective of bank financing. We assume that good environmental information disclosure quality can help companies obtain bank loan, and then test this conjecture through empirical methods. The data of 330 listed companies in China’s heavy polluting industries were collected, and then analysed by SPSS for regression. The result shows that EID is positively related to the scale of corporate bank loan, which means the improvement of EID can bring convenience when companies need bank loans. The research clarifies the financial consequences of EID and provides some enlightenment for the improvement of corporate environmental disclosure quality.

Focusing on the quality of corporate environmental accounting information disclosure (EID), this paper attempts to explore the impact of financial performance on environmental information disclosure. We take listed companies in Chinese heavily polluting industries as the research object, and construct a multiple regression model for data analysis via SPSS. According to Chinese practice, we divide the financial indicators into four areas: solvency, operating capacity, profitability and development capacity, and select four indicators to represent them. The empirical results show that net working capital, current asset turnover and equity growth rate are positively correlated with EID, and return on total assets is negatively correlated with EID. This result means that the solvency, operating ability and development ability in financial performance can promote the improvement of EID, but profitability cannot.

Ulcerative colitis (UC), affecting millions of patients worldwide, is associated with disorders of the gut microbiota. Probiotics‐based therapy positively regulating the community structure of gut microbiota is regarded as an efficient intervention for UC. However, oral probiotics delivery is restricted by limited bioactivity, short retention time, complex pathological condition, and single therapeutic efficacy. Here, a bioengineered probiotic decorated with a multifunctional prodrug coating is constructed to ameliorate the aforementioned shortcomings. The results of UC mice induced by dextran sulfate sodium demonstrate that the intrinsic features of the fabricated coating integrate gut microbes protection, colon‐targeted drug release, prolonged drug retention, and inflammation regulation. In parallel, the probiotics Lactobacillus rhamnosus GG (LGG) could regulate the composition of the gut microbiota and improve epithelial barrier function, thereby synergistically ameliorating UC. These results provide ample shreds of evidence of the therapeutic effect on UC, therefore, demonstrate a great promise as the potential therapeutic strategy for UC treatment. [ABSTRACT FROM AUTHOR]