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Out‐of‐plane polarization is a highly desired property of two‐dimensional (2D) ferroelectrics for application in vertical sandwich‐type photoferroelectric devices, especially in ultrathin ferroelectronic devices. Nevertheless, despite great advances that have been made in recent years, out‐of‐plane polarization remains unrealized in the 2D hybrid double perovskite ferroelectric family. Here, from our previous work 2D hybrid double perovskite HQERN ((S3HQ)4EuRb(NO3)8, S3HQ=S‐3‐hydroxylquinuclidinium), we designed a molecular strategy of F‐substitution on organic component to successfully obtain FQERN ((S3FQ)4EuRb(NO3)8, S3FQ=S‐3‐fluoroquinuclidinium) showing circularly polarized luminescence (CPL) response. Remarkably, compared to the monopolar axis ferroelectric HQERN, FQERN not only shows multiferroicity with the coexistence of multipolar axis ferroelectricity and ferroelasticity but also realizes out‐of‐plane ferroelectric polarization and a dramatic enhancement of Curie temperature of 94 K. This is mainly due to the introduction of F‐substituted organic cations, which leads to a change in orientation and a reduction in crystal lattice void occupancy. Our study demonstrates that F‐substitution is an efficient strategy to realize and optimize ferroelectric functional characteristics, giving more possibility of 2D ferroelectric materials for applications in micro‐nano optoelectronic devices. [ABSTRACT FROM AUTHOR]

Slat aerodynamic noise is largely dependent on its structure parameters(geometric position and variable outline). The analysis of the effects of these two parameters on the features of flow and aerodynamic noise for an airfoil is an effective method of developing techniques for the slat noise suppression. On the basis of three-element airfoil model 30P-30N, the flow field analysis model is established. The RANS and LES(large-eddy simulation) methods are used to analyze the steady and transient state flow field characteristics of the airfoils with typical geometric positions(overlap length, gap width and rotation angle) and morphed profiles(curved close gap of slat tailing edge respectively, which can obtain the corresponding distributions of pressure and turbulent kinetic energy of airfoil, and transient state pressure distribution of flow field. The FW-H acoustic analogy integral method is employed to solve the far-field noise distribution characteristic. The inter-relationship of various slat structure parameters with the far-field acoustic pressure level and its directional distribution features are investigated. According to various slat structure parameters, the coupling relationship between slat noise suppression and corresponding airfoil lift change is analyzed. The results show that the adjustment of slat geometry position and structural deformation parameters can effectively reduce the far-field noise radiation, but the lift coefficient can be reduced to some extent when the angle of attack is increased.

Patients with inflammatory bowel disease, psoriasis or other rheumatic diseases treated with corticosteroids, immunomodulators and biologics might face additional risk during COVID-19 epidemic due to their immunocompromised status. However, there was still no unanimous opinion on the use of these therapy during COVID-19 epidemic. Current studies suggested that systemic corticosteroids might increase the risk of hospitalization, as well as risks of ventilation, ICU, and death among patients with immune-mediated inflammatory diseases. Anti-TNF agent was associated with lower rate of hospitalization, as well as lower risks of ventilation, ICU, and death. No significant changes in rates of hospitalization, ventilation, ICU and mortality were observed in patients treated with immunomodulators or biologics apart from anti-TNF agents. The underlying mechanism of these results might be related to pathway of antiviral immune response and cytokine storm induced by SARS-COV-2 infection. Decision on the use of corticosteroids, immunomodulators and biologics should be made after weighing the benefits and potential risks based on individual patients.

Sea cucumber (Apostichopus japonicus) is considered to be an important food and nourishing ingredient in Asian cuisine, but consumers are vulnerable to food safety risks because of eating customs and breeding conditions. Three isolates (CH, HB, and WH) of Bacillus cereus were obtained from sea cucumbers in three coastal aquaculture areas in northeastern China. We performed whole genome sequencing and the complete genome of each isolate was composed of one circular chromosome, which was further analyzed. COG functional categories, pathogenic bacteria virulence factors and evolutionary relationships were investigated. Virulence factor database (VFDB) analysis demonstrated that all three B. cereus isolates possessed multiple potential virulence factors, which indicates the urgent need to improve microbial detection in aquatic products to ensure seafood security in China.

Although diatom records from lake sediments have been used for quantitative paleoclimatic reconstruction, their validity and sensitivity have rarely been tested rigorously. At Yunlong Lake, an alpine lake in Southwest China, we studied the seasonal succession of diatom assemblages to produce a mean surface water temperature (MSWT) transfer function. In addition, based on the spatial distribution of surface diatom assemblages with water depth, we produced a diatom-water depth (WD) transfer function. Combined with the analysis of diatom assemblages in a sediment core (YL2013-A), changes in surface water temperature and water level over the last ∼100 years were quantitatively reconstructed using the diatom-based transfer functions. Comparison with records of regional meteorology and reservoir water capacity revealed that the diatom-based lake water level reconstruction is a sensitive indicator of short-term fluctuations in precipitation, and it also reflects a long-term stepwise rise in water level caused by the impounding and large-scale extension of the reservoir. In addition, the diatom-inferred MSWT is consistent with the changes in air temperature prior to large-scale human disturbance of the site. However, after the extension of the reservoir, although the regional air temperature continued to increase, the water temperature decreased substantially. This suggests that the large increase in lake water volume in the short term led to a decrease in the average water temperature, which in turn led to the occurrence of a diatom bloom in the cold season. The results demonstrate that diatom transfer functions based on modern observations of the same lake has a high environmental sensitivity and can be used for the quantitative reconstruction of regional climate change. Overall, our findings provide a foundation for the use of lake diatom records for quantitative paleoclimatic reconstruction on various timescales.

The accurate evaluation and fair comparison of wind farms power generation performance is of great significance to the technical transformation and operation and maintenance management of wind farms. However, problems exist in the evaluation indicator systems such as confusion, coupling and broadness, and the influence of wind energy resource differences not being able to be effectively eliminated, which makes it difficult to achieve the fair comparison of power generation performance among different wind farms. Thus, the evaluation indicator system and comprehensive evaluation method of wind farm power generation performance, including the influence of wind energy resource differences, are proposed in this paper to address the problems above, to which some new concepts such as resource conditions, ideal performance, reachable performance, actual performance, and performance loss are introduced in the proposed indicator system; the combination of statistical and comparative indicators are adopted to realize the quantitative evaluation, indicator decoupling, fair comparison, and loss attribution of wind farm power generation performance. The proposed comprehensive evaluation method is based on improved CRITIC (Criteria Importance though Intercrieria Correlation) weighting method, in which the uneven situation of different evaluation indicators and the comprehensive comparison of power generation performance among different wind farms shall be overcome and realized. Several sets of data from Chinese wind farms in service are used to validate the effectiveness and applicability of the proposed method by taking the comprehensive evaluation models based on CRITIC weighting method and entropy weighting method as the benchmarks. The results demonstrated that the proposed evaluation indicator system works in the quantitative evaluation and fair comparison of wind farm design, operation, and maintenance and traces the source of power generation performance loss. In addition, the results of the proposed comprehensive evaluation model are more in line with the actual power generation performance of wind farms and can be applied to the comprehensive evaluation and comparison of power generation performance of different wind farms.

Suicide has become a critical concern, necessitating the development of effective preventative strategies. Social media platforms offer a valuable resource for identifying signs of suicidal ideation. Despite progress in detecting suicidal ideation on social media, accurately identifying individuals who express suicidal thoughts less openly or infrequently poses a significant challenge. To tackle this, we have developed a dataset focused on Chinese suicide narratives from Weibo's Tree Hole feature and introduced an ensemble model named Text Convolutional Neural Network based on Social Network relationships (TCNN-SN). This model enhances predictive performance by leveraging social network relationship features and applying correction factors within a weighted linear fusion framework. It is specifically designed to identify key individuals who can help uncover hidden suicidal users and clusters. Our model, assessed using the bespoke dataset and benchmarked against alternative classification approaches, demonstrates superior accuracy, F1-score and AUC metrics, achieving 88.57%, 88.75% and 94.25%, respectively, outperforming traditional TextCNN models by 12.18%, 10.84% and 10.85%. We assert that our methodology offers a significant advancement in the predictive identification of individuals at risk, thereby contributing to the prevention and reduction of suicide incidences. [ABSTRACT FROM AUTHOR]

Leading edge slat configurations can affect the flow field features of multi-element airfoil, and also have an impact on the distributions of slat noise sources. Based on LES(large eddy current simulation) simulations and FW-H integration equation, together with the typical multi-element airfoil 30P-30N model, the flow characteristics and far field noise features are investigated. Through adjustment of slat configurations, the sensitivity of slat noise radiation to slat position parameters is analyzed. The position parameter features are studied by keeping high aerodynamic performances and effectively attenuating slat noise. The study shows, with fixed slat gap and overlap, slightly decreasing slat deflection angle could effectively reduce slat noise without any compromise with aerodynamic performance; If continuing decrease the slat deflection angle, the slat noise will be increased. On the condition of fixed deflection angle, decreasing gap width, meanwhile increasing overlaps can suppress slat noise to certain degree. Optimizing the slat position parameters is an effective way to improve the wing aerodynamic performance and control the slat noise.

The results of angular and range estimation by conventional signal processing will be far away from true values in the case of unresolved targets due to the merged measurement. In this article, the authors propose a method to localise unresolved targets for frequency diverse array (FDA) radar. Adopting the configurations of subarray-based FDA and full-band FDA as transmitter and receiver, the transmit and receive beampatterns of system are both decoupled in range and angle demands. Furthermore, the receive beamwidth is only a quarter of transmit in range. With the wide transmit beam and narrow receive beam, the authors divide the resolution cell containing unresolved targets into four parts to process separately. A method of intra-pulse beam scanning is proposed to suppress the interference from the targets out of receive beam. Several simulation results demonstrate the effectiveness of the proposed method in the localisation of unresolved targets.

Hepatocellular carcinoma (HCC) does not respond well to current treatments, even immune checkpoint inhibitors. PD‐L1 (programmed cell death ligand 1 or CD274 molecule)‐mediated immune escape of tumor cells may be a key factor affecting the efficacy of immune checkpoint inhibitor (ICI) therapy. However, the regulatory mechanisms of PD‐L1 expression and immune escape require further exploration. Here, we observed that DDX1 (DEAD‐box helicase 1) was overexpressed in HCC tissues and associated with poor prognosis in patients with HCC. Additionally, DDX1 expression correlated negatively with CD8+ T cell frequency. DDX1 overexpression significantly increased interferon gamma (IFN‐γ)‐mediated PD‐L1 expression in HCC cell lines. DDX1 overexpression decreased IFN‐γ and granzyme B production in CD8+ T cells and inhibited CD8+ T cell cytotoxic function in vitro and in vivo. In conclusion, DDX1 plays an essential role in developing the immune escape microenvironment, rendering it a potential predictor of ICI therapy efficacy in HCC. [ABSTRACT FROM AUTHOR]

High-throughput approaches have opened new opportunities for understanding biological processes such as persistent virus infections, which are widespread. However, the potential of persistent infections to develop towards pathogenesis remains to be investigated, particularly with respect to the role of host metabolism. To explore the interactions between cellular metabolism and persistent/pathogenic virus infection, we performed untargeted and targeted metabolomic analysis to examine the effects of Cricket paralysis virus (CrPV, Dicistroviridae) in persistently infected silkworm Bm5 cells and acutely infected Drosophila S2 cells. Our previous study (Viruses 2019, 11, 861) established that both glucose and glutamine levels significantly increased during the persistent period of CrPV infection of Bm5 cells, while they decreased steeply during the pathogenic stages. Strikingly, in this study, an almost opposite pattern in change of metabolites was observed during different stages of acute infection of S2 cells. More specifically, a significant decrease in amino acids and carbohydrates was observed prior to pathogenesis, while their abundance significantly increased again during pathogenesis. Our study illustrates the occurrence of diametrically opposite changes in central carbon mechanisms during CrPV infection of S2 and Bm5 cells that is possibly related to the type of infection (acute or persistent) that is triggered by the virus.