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Streak tube imaging lidar (STIL) can obtain 4-D images of a target, and its performance is mainly determined by the streak tube sensor. To obtain a large field of view, we developed a streak tube with a photocathode length as large as 35.3 mm, which is larger than the commonly used ST-HDR (30 mm). At the same time, the temporal resolution and dynamic spatial resolution are 60 ps and 12 lp/mm, which are very suitable to obtain accurate target coordinates for 4-D imaging. In addition, the streak tube has a high detection sensitivity of 46 mA/W at 500 nm and, hence, prospects in remote imaging. To test the performance of the streak tube, an underwater STIL experiment was conducted. Echo signal processing was performed by means of a bandpass filter and a matched filter, and then the peak detection algorithm was used to reconstruct the image. The results indicate that a spatial resolution better than 9 mm is achieved in the limpid water with a depth of 20 m, and a range accuracy of 1 cm is achieved in the turbid water with a depth of 10 m. Such a performance suggests that the large-field streak tube is of great potential for underwater target imaging and other remote imaging applications.

The point pop-ups in the weather map interface are essential for displaying real-time weather information in different geographic environments. However, with the explosive development of multimodal map information, the unfriendly expression of most pop-ups breaks the smooth user experience, which brings great challenges to the visual design of pop-ups. This paper regarded point pop-ups in the Chinese weather map as the research object and discussed the design strategy of pop-ups from four aspects: information capacity, combination type, layout mode, and transparency. By comparing the design schemes of different factor levels, the user's behavior performance in the two groups of experiments was analyzed. The results found that the behavior performance on graphic-text pop-ups was better than text-only ones at the same level. When point pop-ups were distributed in the weather map interface with high density, the operability and readability of comprehensive weather information could be ensured by adjusting the overlapping and transparency.

The increasing maturity of Internet information technology has led to the rapid rise of blockchain technology. In essence, a blockchain is a shared database. In recent years, blockchain technology has attracted the attention of the public and society. With the continuous development of the market economy, many domestic enterprises have grown in size. At the same time, companies are also faced with various risks, and business risks will have a great impact on the company’s production. This article aims to prevent the business risk of Internet information security platform enterprises based on blockchain technology. Through the PoS algorithm, PoW algorithm, secure hash algorithm, and the principle of direct trust, the Internet information security platform is designed. Firstly, the platform is used for a business risk test with a small company, and the platform satisfaction survey is conducted on the employees of the company. The test results show that the subplatform design reduces the business risk of the company by 5%–10%, and employee satisfaction is high. The signature simulation of this algorithm under the same conditions as the SMRA and RSAR methods is also carried out. The results show that the performance of this algorithm is better. This study opens up a new path for small and medium-sized enterprises to prevent business risks.

Through the analysis of user research methods and the combination of user research methods and the three-layer theory of emotional design, this paper proposes a new mental model construction method, namely the Hierarchical Elicitation Approach. Taking the information architecture design of the emergency monitoring platform as an example, this paper uses the Hierarchical Elicitation Approach to measure the performance rules of users’ minds in the emergency monitoring platform, designs the construction experiments of the macro-mental model and meta-mental model of the system, and optimizes the design according to the experimental results. Moreover, Cogtool is used to analyze the effect of optimization design and verify the application value of the Hierarchical Elicitation Approach in the study of user’s mind.

The visual map elements of the thematic meteorological interface have an essential impact on the user’s processing efficiency. Based on the different visual hierarchies of map site information, including shape, colour, and area, this paper explored the influence of site information’s visual hierarchy change mechanism on user behaviour performance. The results were as follows: 1) The greater the number of shapes, the more difficult it was to complete the task. Therefore, the shape of map sites could be formulated according to the type of meteorological disaster. 2) Under the same comparison level, when the number of colours for multiple map sites was 6, the user’s task operation efficiency was best. 3) The area of map sites was reasonably enlarged within a specific range that could improve the operation efficiency of interface tasks and balance the information complexity of map sites. The results have certain reference value for the visual hierarchy design of map sites in the meteorological interface.

Illegal addition of low-dose multi-component residue of hormone-like compounds have sprung up in human activities and production as a cunning strategy to escape from sanitation monitoring, sowing a horrible seed for accidents in food security. Hence, combined strategies with accuracy and efficiency are urgently needed to overcome current circumstance and practical hurdles. Herein, an integrated analysis that compromises recombinant gene yeast bioassay (V400E-YES) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) determination was developed promptly with distinguishing advantage as optimized V400E-YES provides a sum of hormone-like compounds in sample, and subsequent HPLC-MS analysis can accurately quantify the concentration of compounds. In terms of V400E-YES, large-scale random mutagenesis was performed to obtain higher sensitivity hormone receptors. Excitingly, single mutation of estrogen receptor (ER) at V400E and amphimutation of androgen receptor (AR) at G581R/D831E conferred the highest detection sensitivity with a more than 10-fold increase. Subsequently, sensitive HPLC-MS methods for simultaneous detection of eleven estrogens and nine androgens, respectively, were well-constructed. Utilizing this integrated and validated methods, we successfully investigated the hormone residue in environmental samples from farms in Jiangsu, China. Collectively, with multiple estrogens and androgens residue are being widely detected in soil and sewage samples, the feasibility of this method is highlighted, as well as the increasing lurking peril of hormone-like substance residues in environment.

The antibiotic resistance crisis is becoming incredibly thorny due to the indiscriminate employment of antibiotics in agriculture and aquaculture, such as growth promoters, and the emergence of bacteria that are capable of enduring antibiotic treatment in an endless stream. Hence, to reverse this situation, vigorous efforts should be made in the process of identifying other alternative strategies with a lower frequency of resistance. Antimicrobial peptides (AMPs), originated from host defense peptides, are generally produced by a variety of organisms as defensive weapons to protect the host from other pathogenic bacteria. The unique ability of AMPs to control bacterial infections, as well as low propensity to acquire resistance, provides the basis for it to become one of the promising antibacterial substances. Herein, we present new insights into the biological functions, structural properties, distinct mechanisms of action of AMPs and their resistance determinants. Besides, we separately discuss natural and synthetic AMPs, including their source, screening pathway and antibacterial activity. Lastly, challenges and perspectives to identify novel potent AMPs are highlighted, which will expand our understanding of the chemical space of antimicrobials and provide a pipeline for discovering the next-generation of AMPs.

It is known that the elderly population has weak immune functioning and is a susceptible and high-risk group with respect to the current coronavirus disease 2019 (COVID-19) epidemic. In this study, to understand the influencing factors of COVID-19-related risks and coping behaviors of elderly individuals with respect to COVID-19 and to provide a basis for taking corresponding protective measures, a questionnaire survey was applied to an elderly population. One-way analysis of variance (ANOVA) and linear regression analysis were used to explore the influencing factors of the level of understanding of COVID-19 risks among the elderly population. Additionally, the chi-square test and logistic regression analysis were used to explore the influencing factors of the elderly population&rsquo, s protective behaviors against COVID-19. This study found: (1) The sex, age, and self-care ability of elderly individuals were significantly correlated with their level of understanding of COVID-19, and that those who were female, were of a younger age, or had better self-care ability had higher levels of understanding, (2) The sex, place of residence, and level of understanding of COVID-19 among the elderly individuals were significantly correlated with their protective behaviors, e.g., those who were women, had high levels of understanding, and lived in cities were more likely to have good behaviors, (3) Elderly individuals&rsquo, assessments of COVID-19 information provided by the government were significantly correlated with their protective behaviors&mdash, those who had a positive evaluation of relevant information provided by the government were more likely to develop protective behavior. The conclusions of this study show that it is crucial to implement COVID-19 prevention and control measures in the elderly population. Society, communities, and families need to increase their concerns about the health and risk awareness of the elderly individuals.

Antibiotic tolerance, the ability of a typically susceptible microorganism to survive extended periods of exposure to antibiotics, has a critical role in chronic and recurrent bacterial infections, and facilitates the evolution of antibiotic resistance. However, the physiological factors that contribute to the development of antibiotic tolerance, particularly in vivo, are not fully known. Despite the fact that a high-fat diet (HFD) is implicated in several human diseases, the relationship between HFD and antibiotic efficacy is still poorly understood. Here, we evaluated the efficacy of multiple clinically relevant bactericidal antibiotics in HFD-fed mice infected with methicillin-resistant Staphylococcus aureus (MRSA) or Escherichia coli. We found that HFD-fed mice had higher bacterial burdens and these bacteria displayed lower susceptibility to bactericidal antibiotic treatment compared with mice that were fed a standard diet, while microbiota-depleted standard-diet- or HFD-fed mice showed similar susceptibility. Faecal microbiota transplantation from HFD-fed mice impaired antibiotic activity in mice fed a standard diet, indicating that alteration of the gut microbiota and related metabolites in HFD-fed mice may account for the decreased antibiotic activity. 16S rRNA sequencing and metabolomics analysis of faecal samples revealed decreased microbial diversity and differential metabolite profiles in HFD-fed mice. Notably, the tryptophan metabolite indole-3-acetic acid (IAA) was significantly decreased in HFD-fed mice. Further in vitro studies showed that IAA supplementation inhibited the formation of bacterial persisters and promoted the elimination of persisters in combination with antibiotic treatment, potentially through the activation of bacterial metabolic pathways. In vivo, the combination of IAA and ciprofloxacin increased the survival rate of HFD-fed mice infected with MRSA persisters. Overall, our data reveal that a HFD has an antagonistic effect on antibiotic treatment in a mouse model, and this is associated with the alteration of the gut microbiota and IAA production. High-fat diet decreases antibiotic efficacy in a mouse model via an altered gut microbiota and decreased indole-3-acetic acid, which potentially converts tolerant bacterial cells into susceptible metabolically active cells.

The rapid dissemination of antibiotic resistance by horizontal gene transfer (HGT) renders the global resistance crisis more tense and urgent as few effective antimicrobials are available to combat multidrug-resistant (MDR) pathogens at present. Conjugation is one of the most dominant and representative pathways of HGT. Antibiotic residue in environment is recognized as an important accelerator for conjugal transfer, whereas the roles of non-antibiotic pharmaceuticals in this process are not fully understood. Here we found that environmentally relevant concentrations of paclitaxel as well as its derivative docetaxel, two commonly used anticancer drugs, remarkably facilitated the conjugative transfer of resistance plasmids carrying multiple antibiotic resistance genes (ARGs). The underlying mechanisms accounting for the enhanced conjugation were investigated by detecting the activity of RpoS regulon, membrane permeability, SOS response and gene expression of conjugative transfer systems. Our results showed that paclitaxel induced a series of cellular responses, including up-regulation of rpoS expression, activated SOS response, increased cell membrane permeability, enhanced plasmid replication and mating pilus formation. Collectively, our data provide new insight on the roles of paclitaxel and its derivative in promoting the conjugal transfer of ARGs, highlighting the importance of good antimicrobial stewardship.

The widespread dissemination of antibiotic resistance genes (ARGs) is a serious problem and constitutes a threat for public health. Plasmid-mediated conjugative transfer of ARGs is recognized as one of the most important pathways accounting for this global crisis. Inhibiting the conjugative transfer of resistant gene-bearing plasmids provides a feasible strategy to prevent the spread of antibiotic resistance. Here we found that melatonin, a neurohormone secreted from pineal gland, substantially inhibited the horizontal transfer of RP4-7 plasmid in a dose-dependent manner. Furthermore, melatonin could also suppress the conjugal frequency of different types of clinical plasmids that carrying colistin resistance gene mcr-1 rather than blaNDM or tet(X) genes. Next, we investigated the mechanisms underlying the inhibitory effect of melatonin on conjugation. As a result, we showed that the addition of melatonin markedly reduced bacterial membrane permeability and inhibited the oxidative stress. In line with these observations, the conjugative transfer-related genes were regulated accordingly. Most importantly, we uncovered that melatonin disrupted bacterial proton motive force (PMF), which is an essential bacterial energy metabolism substance and is important for conjugative process. Collectively, these results provide implications that some non-antibiotics such as melatonin is an effective inhibitor of transmission of ARGs and raises a promising strategy to confront the increasing resistant infections.

Based on the customer satisfaction index model, we constructed an elderly care service satisfaction model that includes 5 latent variables and 16 observed variables. To analyze the degree of satisfaction of elderly individuals in nursing homes, we used structural equation model (SEM) to test the nursing service elderly satisfaction model. With the help of AMOS 22.0 software, we analyzed the degree of model fit and the behavioral relationships between the variables that affect the path. We found that the satisfaction of Chinese urban elderly individuals in nursing homes is at a moderate level, which is lower than the quality expected by elderly individuals. The customer satisfaction index model can be applied to assess satisfaction with nursing services. Furthermore, perceived quality and value have a significant impact on satisfaction.

Due to discrimination and media literacy, middle-aged and elderly individuals have been easily reduced to marginalized groups in the identification of rumours during a public health crisis and can easily spread rumours repeatedly, which has a negative impact on pandemic prevention and social psychology. To further clarify the factors influencing their behaviours, this study used a questionnaire to survey a sample of 556 individuals in China and used multiple linear regression and analysis of variance to explore influencing factors during the coronavirus disease 2019 (COVID-19) pandemic. We found that, first, in the COVID-19 pandemic, middle-aged and elderly adults&rsquo, willingness to re-spread rumours is positively related to their degree of believing rumours and to personal anxiety and is negatively related to their rumour-discrimination ability and to their perception of serious consequences to rumour spreading. Second, the degree of believing rumours plays an intermediary role in the willingness to re-spread rumours. It plays a partial mediating role in the path of anxiety&rsquo, s influence on behaviour, suggesting that an anxious person will spread a rumour even if he or she does not have a strong belief in the rumour. Third, interpersonal communication has a greater credibility and a greater willingness to re-spread than does mass communication. This suggests the importance of increasing public knowledge expertise and of reducing public panic. This also has important implications for the future design of public health policies.

Yang, B., 2020. Performance evaluation model of economic compensation policy for cultivated land protection in coastal areas based on propensity value matching method. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 19–23. Coconut Creek (Florida), ISSN 0749-0208.In order to promote the rapid economic growth of cultivated land protection in coastal areas a performance evaluation model of economic compensation policy for cultivated land protection in coastal areas was designed based on the propensity value matching method. According to the principle of remolding the economic protection value of cultivated land resources in coastal areas, the compensation model of cultivated land protection economic policy is established based on the propensity value matching method, and then the market value of cultivated land protection economy in coastal areas is calculated based on the performance evaluation elements, so as to realize the performance tendency value calculation of economic compensation policy. The empirical results show that, with the support of the propensity value matching method, the economic compensation policy of cultivated land protection in coastal areas shows an obvious trend of rapid growth within a given period of time, and the overall performance evaluation environment in the region is gradually improved.