Search

The distribution law of UHF electromagnetic field strength in rectangular tunnel was studied by use of geometrical optics model and experimental data, and conclusion was obtained: there are apparently different electromagnetic field distributions when transmitting antenna is located in different positions of a tunnel section. When the antenna is in the middle of the tunnel, the fast fading convergence speed is the fastest and received electromagnetic field strength is the maximum. The electromagnetic field strength exhibits a nearly cosine scattering distribution, while it distributes relatively even when the location of transmitting antenna is nearby the tunnel wall. The conclusion can be used to predict effective coverage range of electromagnetic field in tunnels, and is useful for design and detection of cellular personal mobile communication network in tunnels.

SUMMARY: Panicle development is an important determinant of the grain number in rice. A thorough characterization of the molecular mechanism underlying panicle development will lead to improved breeding of high‐yielding rice varieties. Frizzy Panicle (FZP), a critical gene for panicle development, is regulated by OsBZR1 and OsARFs at the transcriptional stage. However, the translational modulation of FZP has not been reported. We reveal that the CU‐rich elements (CUREs) in the 3′ UTR of the FZP mRNA are crucial for efficient FZP translation. The knockout of CUREs in the FZP 3′ UTR or the over‐expression of the FZP 3′ UTR fragment containing CUREs resulted in an increase in FZP mRNA translation efficiency. Moreover, the number of secondary branches (NSB) and the grain number per panicle (GNP) decreased in the transformed rice plants. The CUREs in the 3′ UTR of FZP mRNA were verified as the targets of the polypyrimidine tract‐binding proteins OsPTB1 and OsPTB2 in rice. Both OsPTB1 and OsPTB2 were highly expressed in young panicles. The knockout of OsPTB1/2 resulted in an increase in the FZP translational efficiency and a decrease in the NSB and GNP. Furthermore, the over‐expression of OsPTB1/2 decreased the translation of the reporter gene fused to FZP 3′ UTR in vivo and in vitro. These results suggest that OsPTB1/2 can mediate FZP translational repression by interacting with CUREs in the 3′ UTR of FZP mRNA, leading to changes in the NSB and GNP. Accordingly, in addition to transcriptional regulation, FZP expression is also fine‐tuned at the translational stage during rice panicle development. Significance Statement: Panicle architecture plays an important role in grain number determination in rice. Here, we identified a conserved RNA element, CU‐rich element (CURE), at the 3′‐untranslated region of Frizzy Panicle (FZP) which is a well‐studied gene regulating panicle development in rice. The CUREs could recruit the binding proteins OsPTB1/2 to repress the translation of FZP itself, which regulates the differentiation of secondary branches in panicle development. [ABSTRACT FROM AUTHOR]

• H-SIA, BN and experimental data are integrated to quantify human errors. • Effects of five PSFs on human performance are analyzed. • The results benefit human reliability analysis of human-autonomy collaboration. Human-autonomy collaboration plays a pivotal role in the development of Maritime autonomous surface ships (MASS), as Shore control center (SCC) operators may engage in the control loop by directly operating the MASS, or, in the supervisory loop, monitoring the MASS and taking over control when needed. Thus, effective human performance during takeover control and operation is crucial for the safety of MASS operations. However, since the MASS is still in the early phase of development, the mechanism of human errors is unknown, and the data on human-autonomy collaborative operation is scarce. Human reliability analysis (HRA) aims to assess human errors qualitatively and quantitatively, and is widely used in various complex systems to help safety analysis. This study is dedicated to incorporating advanced HRA methods elements to identify and quantify human errors during taking over control and operation of a MASS in collision avoidance scenarios. It presents virtual experimental results, combined with theoretical human error identification and assessment methods. At first, we apply the Human-System Interaction in Autonomy (H-SIA) method to identify potential human errors; secondly, we identify relevant Performance Shaping Factors (PSFs) including Experience, Boredom, Task complexity, Available time and Pre-warning, and performance measures of the human errors, and implement them in the virtual experiment based on a full-scale autonomous ferry research vessel called milliAmpere2. Finally, we build a Bayesian Network (BN) to present causal and probabilistic relationships between PSFs and human errors through experimental data. The results show that available time has the highest impact on takeover performance of operators, followed by task complexity and pre-warning. Boredom does not present a significant sole impact unless combined with available time. Experience does not show a significant impact on human performance. In addition to the relevance of the human errors analysis to the safe development and operational design of MASS, the developed method benefits other human-autonomy collaborative systems. The developed BN model shows adaptability to assess human error probabilities, and the practical significance of integrating experimental data into the existing HRA methodologies for complex systems. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of Treg/Th1 imbalance in cadmium-induced lung injury and the potential protective effect of astilbin against cadmium-induced lung injury in chicken. Cadmium exposure significantly decreased T-AOC and GSH-Px levels and SOD activity in the chicken lung tissues. In contrast, it significantly increased the MDA and NO levels. These results indicate that cadmium triggers oxidative stress in lungs. Histopathological analysis revealed that cadmium exposure further induced infiltration of lymphocytes in the chicken lungs, indicating that cadmium causes pulmonary damage. Further analysis revealed that cadmium decreased the expression of IL-4 and IL-10 but increased those of IL-17, Foxp3, TNF-α, and TGF-β, indicating that the exposure of cadmium induced the imbalance of Treg/Th1. Moreover, cadmium adversely affected chicken lung function by activating the NF-kB pathway and inducing expression of genes downstream to these pathways (COX-2, iNOS), associated with inflammatory injury in the lung tissue. Astilbin reduced cadmium-induced oxidative stress and inflammation in the lungs by increasing antioxidant enzyme activities and restoring Treg/Th1 balance. In conclusion, our results suggest that astilbin treatment alleviated the effects of cadmium-mediated lung injury in chickens by restoring the Treg/Th1 balance. [Display omitted] • Cadmium exposure triggers Treg/Th1 imbalanced and leads to inflammation. • Cadmium can cause inflammation via NF-kB pathway in chicken. • Astilbin regulates inflammation induced by Cd through Treg/Th1 signaling pathway. [ABSTRACT FROM AUTHOR]

The investigation involved the utilization of coastal water microcosms that simulated hydrocarbon pollution with liquid paraffin over a duration of 56 days. An inoculum of Pseudomonas sp. D_192 (P_D192), possessing oil degradability, was introduced into the microcosms to examine the impact of externally fortified bacteria within the background medium on the prokaryotic community during the treatment of hydrocarbon pollution in seawater. Significant disparities in alpha/beta diversity and prokaryotic community composition were observed between microcosms with and without the addition of P_D192 inoculum. The introduction of the P_D192 inoculum was found to expedite the degradation of hydrocarbon pollutants by enhancing the relative abundance of petroleum hydrocarbon-degrading bacteria (especially Alcanivorax sp.) and fortifying metabolic functions associated with xenobiotics biodegradation and hydrocarbon degradation metabolism. Furthermore, the co-occurrence network of the microcosm with P_D192 inoculum exhibited a higher number of positive correlations, indicating an augmentation of facilitative interactions under the influence of Pseudomonas sp. D_192 inoculum. • Inoculum of Pseudomonas sp. D192 (P_D192) accelerate the degradation of hydrocarbon pollutants. • The prokaryotic diversity was significantly changed by adding the P_D192 inoculum. • The inoculum of P_D192 caused more positive associations with hydrocarbon degraders. • The P_D192 inoculum strengthens the metabolic function related to xenobiotic and hydrocarbon biodegradation. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of two global crises, the global financial crisis and the COVID-19 crisis, on herding behavior in the Chinese and U.S. stock markets. We find no evidence of herding behavior during these two global crises in the U.S. stock market, yet significant herding emerges under the COVID-19 crisis in Chinese mainland stock market. Additionally, the observed herding behavior in mainland China is primarily driven by sentiment. Our results reveal and explain the differences in the effects of financial crisis and public health crisis on herding behavior, as well as variations between emerging and developed stock markets. • Examine herding behavior during GFC and COVID-19 in Chinese and U.S. stock markets. • There is no herding during the two global crises in the U.S. stock market. • Herding behavior emerges under the COVID-19 crisis in Chinese mainland stock market. • The observed herding behavior in mainland China is primarily driven by sentiment. [ABSTRACT FROM AUTHOR]

This paper introduces a factor-augmented forecasting regression model in the presence of threshold effects. We consider least squares estimation of the regression parameters and establish asymptotic theories for estimators of both slope coefficients and the threshold parameter. Prediction intervals are also constructed for factor-augmented forecasts. Moreover, we develop a likelihood ratio statistic for tests on the threshold parameter and a sup-Wald test statistic for tests on the presence of threshold effects, respectively. Simulation results show that the proposed estimation method and testing procedures work very well in finite samples. Finally, we demonstrate the usefulness of the proposed model through an application to forecasting stock market returns. [ABSTRACT FROM AUTHOR]