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In this paper, a single-antenna full-duplex subsystem is proposed, consisting of a high isolation network and a stacked patch antenna with reflector. The employed patch antenna is fed by two ports with very similar input impedances to make the reflected signals identical. The high isolation network composed of two hybrids and two circulators plays a crucial part in achieving high transmitting to receiving (Tx-Rx) isolation. It is able to cancel out the inevitable reflected signals from the antenna ports and the leakage signals from the circulators. The theoretical analysis is presented and the subsystem is also fabricated and measured. According to the measurement results, across the operation band from 2.018 to 2.12 GHz, the subsystem has VSWR 50 dB, axial ratio 10.2 dBic. Compared with the state-of-art single-antenna full-duplex subsystems, the proposed design features high Tx-Rx isolation level and high gain, which is suitable for microwave radio relay communication and satellite detection application.

Self-compacting concrete (SCC), known for its excellent fluidity and self-compacting ability, is widely used in civil engineering. To enhance the comprehensive performance of SCC, dolomite powder (DP) is integrated as a substitute for cement. This study aims to analyze the impact of DP on the yield stress relationship between self-compacting mortar (SCM) and self-compacting paste (SCP) from a multi-scale perspective. A new predictive model for the yield stress relationship between SCM and SCP incorporating DP is established by improving the n value in the existing ϕe model, which characterizes the sensitivity of the mortar yield stress relative to changes in the paste yield stress. By conducting mini-slump flow tests on nine sets of cement–DP mixtures, it is found that DP impacts the yield stress relationship between SCM and SCP mainly through changes in the inter-particle filling effect, and the n value in the predictive model is roughly between 2.4 and 3.6. When the DP content is kept constant and the particle size is changed, the n value shows a strong positive linear relationship with the packing density of the paste (ϕe,p). The relationship between n and ϕe,p is derived using the linear fitting method, which improves the model’s predictive accuracy by 95.2%.

Many vision-based bolt looseness detection methods that directly observe the bolts have been developed. However, these methods have many limitations in terms of the conditions and processes of their implementation. To address these problems, this paper proposed a fully automated vision-based bolt looseness detection method for a rigid multi-bolt connection. The proposed method combines digital shearing speckle pattern interferometry (DSSPI) and recurrent neural network (RNN) and involves capturing speckle fringe patterns under various looseness cases using the DSSPI system and classifying these patterns with an RNN model to detect the loose bolts. The proposed method can detect all the bolts within the measured surface at one time, which is efficient. On the other hand, it eliminates the need for prior information such as the initial angle and position of each bolt. It can even detect unseen bolts in multi-bolt connections, making it applicable for connections in complex structures in which occlusion often occurs. Additionally, the method eliminates the complex process of distortion rectification. These features make the method achieve a single-judgment time (four bolts at one detection) of only 4.70 millisecond with a detection accuracy over 99%, which has potential for the real-time detection of loose bolts in multi-bolt connections.

Rabies is an acute zoonotic infectious disease caused by rabies virus. In 2015, the World Health Organization proposed the goal of eliminating dog-induced human rabies by 2030. In response to this goal positively, China has been dedicated to the control and elimination of rabies mainly caused by dogs, for nearly 10 years. By applying infectious disease dynamics, in this paper, we establish a dog-human rabies transmission model to forecast future epidemic trends of rabies, assess whether the goal of eliminating dog-induced human rabies cases in China can be achieved in 2030, and further evaluate and suggest the follow-up sustained preventive measures after the elimination of human rabies. By analyzing and simulating above dynamic model, it is concluded that rabies has been well controlled in China in recent years, but dog-induced human rabies cannot be eliminated by 2030 according to current situation. In addition, we propose to improve rabies control efforts by increasing the immunization coverage rate of rural domestic dogs, controlling the number of stray dogs and preventing the import of rabies virus in wild animals. Immunization coverage rate of rural domestic dogs which is currently less than 10% is far from requirement, and it needs to reach 50%–60% to meet the goal of 2030. Since it is difficult to immunize stray dogs, we suggest to control the number of stray dogs below 15.27 million to achieve the goal. If the goal of eliminating human rabies is reached in 2030, the essential immunization coverage needs to be maintained for 18 years to reduce the number of canine rabies cases to zero. Lastly, to prevent transmission of rabies virus from wild animals to dogs, the thresholds of the number of dogs and the immunization coverage rate of dogs after eliminating canine rabies cases are also discussed.

Medical workers often face serious family-work conflicts and are prone to depressive symptoms. The present study aimed at investigating associations between family-work conflict and depression in emergencies, and at exploring psychological processes involved in this association. A total of 1347 participants were recruited to complete questionnaires. Results showed that the positive effect of family-work conflict on depression was mediated by the basic psychological needs satisfaction, and subjective social status moderated this relationship as a buffer. For individuals with high levels of subjective social status, the direct and indirect effects of family-work conflict on depression were weaker. This study identified the mediating and moderating mechanisms of family-work conflict and depression. The implications of these findings in both theoretical and practical terms will be discussed.

Background. There are very few professional recommendations or guidelines on the needle thoracentesis decompression (NTD) for the tension pneumothorax in the elderly. This study aimed to investigate the safety and risk factors of tension pneumothorax NTD in patients over 75 years old based on CT evaluation of the chest wall thickness (CWT). Methods. The retrospective study was conducted among 136 in-patients over 75 years old. The CWT and closest depth to vital structure of the second intercostal space at the midclavicular line (second ICS-MCL) and the fifth intercostal space at the midaxillary line (fifth ICS-MAL) were compared as well as the expected failure rates and the incidence of severe complications of different needles. We also analyzed the influence of age, sex, presence or absence of chronic obstructive pulmonary disease (COPD), and body mass index (BMI) on CWT. Results. The CWT of the second ICS-MCL was smaller than the fifth ICS-MAL both on the left and the right side (P

Summary: Current photocatalytic uranium (U) extraction methods have intrinsic obstacles, such as the recombination of charge carriers, and the deactivation of catalysts by extracted U. Here we show that, by applying a bias potential on the photocatalyst, the photoelectrochemical (PEC) method can address these limitations. We demonstrate that, owing to efficient spatial charge-carriers separation driven by the applied bias, the PEC method enables efficient and durable U extraction. The effects of multiple operation conditions are investigated. The U extraction proceeds via single-step one-electron reduction, resulting in the formation of pentavalent U, which can facilitate future studies on this often-overlooked U species. In real seepage water the PEC method achieves an extraction capacity of 0.67 gU m−3·h−1 without deactivation for 156 h continuous operation, which is 17 times faster than the photocatalytic method. This work provides an alternative tool for U resource recovery and facilitates future studies on U(V) chemistry.

Under the impact of COVID-19, the status and mechanisms of post-traumatic growth among medical workers facing challenges related to family-work conflict are of great concern. In view of the complex relationship between family-work conflict and post-traumatic growth, the present study sought to explore the specific relationships between family-work conflict and post-traumatic growth as well as the specific roles of positive psychological capital, perceived social support, and suppression. We recruited 1,347 participants. The results revealed that positive psychological capital and perceived social support played mediating roles, while suppression strategies moderated the mediating effect. Compared with the low suppression group, the negative impact of family-work conflict on positive psychological capital and perceived social support was reduced in the high suppression group. Thus, a higher level of suppression was more conducive to post-traumatic growth. The current study enriches and expands the findings of previous studies in theory and provides practical ways to promote post-traumatic growth in medical workers.

The multiscale rheological threshold theory can guide the mix design of self-compacting concrete (SCC) from a trans-scale view. Through the paste thresholds calculated by the mini-slump flow test results, the workability of SCC can be predicted. However, this method shows insufficient prediction accuracy when handling multiplexed powder. In the existing threshold calculation formula, the characteristics of powder materials were described through empirical values, without considering the specific properties of various powders. This paper focuses on the application of the multiscale rheological threshold theory to multiplexed powder SCCs. Through the research on the characteristics of powder materials, especially D50 and Span, the effect of the powder properties on paste thresholds was carried out. The prediction accuracies were confirmed by four sets of self-compacting mixtures at paste and concrete scales and were verified with another set of tests. There are a total of 45 paste and 45 SCC test results with multiplexed powders, including cement, fly ash, and limestone powder. The predicting accuracies are expressed as the relative accuracy ε and the accuracy index ε′, calculated by the comparison of self-compacting zones at paste and SCC scales. The calculation results showed that ε and ε′ of the modified method increased. This modified method can be efficient for the mix design of SCC containing multiplexed powders.

The use of fly ash (FA) limestone and powder (LP) in combination with cement in concrete has several practical, ecological, and economic advantages by reducing carbon dioxide emissions, reducing the excessive consumption of natural resources, and contributing to a cleaner production of self-compacting concrete (SCC). A mix design method for SCC based on paste rheological threshold theory can guide the SCC mix design by paste tests. This method can be visualized by the self-compacting paste zone (SCP zone), a plane area where all the mix points meet the paste threshold theory, and SCC zone, a plane area consisting of all the mix points satisfying the criteria of qualified SCC. In the case of cement SCC, the SCP zone coheres with the SCC zone. However, in the case of the addition of FA or LP with different granulometry and shape characteristics from cement, experimental results indicate that the SCP zone is separated from the SCC zone. This work quantitatively studied the influence of FA and LP on the movement of the SCP zone by introducing the improved powder equivalence model. The improved model was obtained by powder equivalence coefficients calculated through the mortar test results with or without FA or LP, instead of SCC tests in the former method. The equivalence coefficients by volume of FA and LP are 0.55 and 0.79, respectively, which means that 1.82 unit volume of FA or 1.27 unit volume of LP is equivalent to one unit volume of cement. The improved powder equivalence model was verified by the successful preparation of SCC incorporating FA or LP simply and effectively. The equivalent SCP zone cohered better with the SCC zone than the former SCP zone, which could guide the quick mix design of SCC without SCC premix tests.

In order to understand the effect of sand type on the rheological properties of self-compacting mortar, four varieties of sand, namely, quartz sand (QS), river sand (RS), and two kinds of manufactured sand, marked as MS-A and MS-B, were studied. As part of this study, the sands’ particle shape parameters, such as their length:width ratio and roundness, were determined. Mortars containing the four varieties of sand were tested using the slump flow test and the V-funnel test in oven-dried (OD) and saturated surface-dried (SSD) conditions in order to identify the water absorption, shape-related differences, and specific gravity in their rheological performance. The changing trends of the slump flows and the V-funnel times of the different mortars in OD and SSD were similar. By eliminating the influence of water absorption on mortar rheology, shape–weight parameters, such as the ratio between the length:width ratio and specific gravity (LWS) and the product of roundness and specific gravity (ROS), were defined in order to quantify the compound effects of sand type on mortar rheology. The regression analysis showed an excellent linear correlation between slump flow and both LWS and ROS, and a very good linear correlation was also demonstrated between the V-funnel time and both LWS and ROS. Based on the particle shape–weight parameters, the rheological properties of mortars can be predicted. Based on the mortar rheological threshold theory, the self-compacting mortar (SCM) zone can be drawn. The predicted SCM zone overlaps considerably with the experimental SCM zone for MS-A.