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It is crucial that simple and high-throughput methods for determining multiple, or groups of, sulfonamides (SAs) be developed since they are widely used in animal husbandry and aquaculture. We developed a paper-based multicolor colorimetric aptasensor to detect 3 SAs: sulfaquinoxaline (SQ), sulfamethoxypyridazine (SMP) and sulfamethoxydiazine (SMD). Using a broad-specificity aptamer as a bioreceptor, we reduced the growth of nicotinamide adenine dinucleotide I (NADH)–ascorbic acid (AA)-mediated gold nanobipyramids (AuNBPs) to generate a multicolor signal. We also used a paper-based analytical device (PAD) system to deposit AuNBPs for a sensitive color signal read out. The aptasensor can detect more color changes corresponding to the concentrations of SQ, SMP and SMD and has higher sensitivity, better specificity and stability. It can also be used to determine SQ, SMP and SDM individually, or collectively, or any two together with a visual detection limit of 0.3–1.0 µM, a spectrometry quantification limit (LOQ) of 0.3–0.5 µM and a spectrometry detection limits (LOD) of 0.09–0.15 µM. The aptasensor was successfully used to determine SQ, SMP and SDM in fish muscle with a recovery of 89–94% and a RSD n = 5) < 8%, making it a promising method for the rapid screening of total SQ, SMP and SDM residue in seafood. [ABSTRACT FROM AUTHOR]

Simple Summary: Cardiovascular disease is the number one cause of death. Congenital heart defects (CHDs) consist of 24–28% congenital malformation, yet the disease mechanism remains unclear. Zebrafish has been widely used as a model to study gene function, disease mechanism and drug discovery. It was reported that 82% of disease-causing human proteins had an obvious orthologue in zebrafish. We constructed a zebrafish disease model with hoxa1a mutation that exhibited heart malformation like HOXA1-null human patients. By studying heart disease mechanisms in zebrafish, we could further understand related diseases in humans. Mutations in HOXA1 can lead to diseases such as Bosley–Salih–Alorainy syndrome, involving severe cardiovascular malformations. However, the role of HOXA1 in cardiac morphogenesis remains unclear. hoxa1a is a homologous gene to human HOXA1 in zebrafish. We used CRISPR to make hoxa1a-null zebrafish that exhibited multiple heart malformations. In situ hybridization and sections revealed the morphological changes in mutants: enlarged ventricle with thickened myocardium and increased trabeculae, intensified OFT and inadequate heart looping, with electrocardiography supporting these pathological changes. High-speed photography captured cardiac pumping and revealed a significant decrease in cardiac output. Furthermore, lacking hoxa1a led to posterior body abnormality that affected movement ability, corresponding with the motor development delay in patients. Upregulation of hox paralogues in hoxa1a-null fish implied a compensatory mechanism between hox genes. Accordingly, we successfully constructed a hoxa1a-null model with a cardiac disease pattern which occurred in human HOXA1-associated heart malformation. The study of hoxa1a in zebrafish can further promote the understanding of hox genes and related diseases. [ABSTRACT FROM AUTHOR]

After a natural disaster, it is critical to perform a damage assessment of affected buildings rapidly and accurately to meet emergency response requirements. With the development of deep learning (DL) technology, the change detection (CD) method based on fully convolutional networks has been used for disaster analysis and assessment. However, the main limitations of most present methods are their large number of parameters, high computational complexity, and limited deployment equipment resources, which affect the real-time performance of disaster analysis. Therefore, to make a trade-off in the relationship between the accuracy and efficiency of damaged building CD, this research proposes an efficient method based on a lightweight residual block (LRB) in bitemporal high-resolution remote sensing (RS) images (LRBNet). LRBNet is an encoder – decoder structure with the Siamese network and UNet++ as the backbone. It uses our LRB in the whole network to replace the original convolution unit, which can extract features to reduce computational complexity. The LRB consists of the lightweight compression module (LCM) and efficient channel attention (ECA) to learn the essential damage information in the feature map and improve the feature expression ability efficiently. Moreover, the multilevel damage feature aggregation attention module is the last process of the network and performs fine-grained aggregation of the multilevel disaster change features and emphasizes global semantic and spatial information to maximize the representative damage change characteristics. Furthermore, we conducted a series of experiments on the global-scale disaster xBD dataset (including 19 different disaster events). Our method not only accurately evaluated the level of disaster but also had favourable detection efficiency, achieving a good trade-off between recognition accuracy and computational resources. [ABSTRACT FROM AUTHOR]

Long-duration aerodynamic pressure fluctuation in high-speed railway tunnels in the post-train stage causes fatigue damage to tunnel structures and facilities. It increases the risk of accidents and requires in-depth research. This complex phenomenon is caused by the superposition of multiple pressure waves generated successively when a train enters/leaves a tunnel. In this study, the spatial–temporal distribution of the pressure state (SDPS) model was developed, and general equations describing the transient pressure state distribution were given. Furthermore, a prediction method for extreme pressures in tunnels and a fast calculation program were proposed based on the SDPS model. The proposed model was verified using field measurements. Using the SDPS model, the worst conditions of pressure fluctuations in tunnels were analyzed. The results show that most of the maximum positive and negative pressures are symmetrical around the midpoint of the tunnel axis and appear alternately around it. When the train/wave velocity ratio M ≤ 0.8 and the train/tunnel length ratio ε ≤ 0.8, the dimensionless position of the maximum peak-to-peak pressure region was concentrated in the region of [0.33,0.67] in the tunnel, indicating the location of potential fatigue damage. The proposed model is helpful in building safe and sustainable transportation systems. [ABSTRACT FROM AUTHOR]

The speed of earthquake emergency web document data cleaning is one of the key factors affecting emergency rescue decision-making. Data classification is the core process of data cleaning, and the efficiency of data classification determines the speed of data cleaning. This article is based on earthquake emergency Web document data and HTML structural features, combined with TF-IDF Algorithm and information calculation model, improves the word frequency factor and location factor parameters, and proposes the weighted frequency algorithm P-TF-IDF for earthquake emergency Web documents. To filter out less frequent words and optimize the FastText model, N-gram Feature word vectors effectively improve the efficiency of Web document data classification; for text classification data, use missing data recognition rules, data classification rules, and data repair rules to design an artificial intelligence-based earthquake emergency network information data cleaning framework to detect invalid data sets value, complete data comparison and redundancy judgment, clean up data conflicts and data errors, and generate a complete data set without duplication. The data cleaning framework not only completes the fusion of earthquake emergency network information but also provides a data foundation for the visualization of earthquake emergency data. [ABSTRACT FROM AUTHOR]

In this paper, a three‐dimensional simulation model of the engine cylinder is established using commercial simulation software AVL‐Fire, and the accuracy of the model is verified with experimental results. The effects of diesel/biodiesel/n‐butanol blends on diesel engine performance, and combustion and emissions characteristics were investigated by performing simulation operations on the model. The combustion process in the cylinder was simulated for 0%, 5%, 10%, 15%, and 20% of n‐butanol in the fuel mixture. The results showed that at 75% load, the brake thermal efficiency of D95N5, D90N10, D85N15, and D80N20 engines increased by 0.84%, 1.68%, 2.48%, and 3.19%, respectively, and soot emissions decreased by 2.76%, 5.52%, 8.25%, and 10.96%, respectively, compared with D100. However, the brake power of the engine was reduced, the brake ratio fuel consumption increased, and NOx emission increased. In addition, at all loads, soot and CO emissions decrease as the percentage of n‐butanol in the fuel mixture increases. [ABSTRACT FROM AUTHOR]

The corrosion properties of AISI 316L stainless steel in upward slug flow were initially investigated using the electrochemical measurements and computational fluid dynamics (CFD) simulations. The results demonstrate that the slug flow may destroy the passivation film on the specimen surface due to its intermittency and volatility, accelerating the pitting corrosion process on the electrode surface. It results in a higher corrosion rate in the two-phase slug flow than in the single-phase flow. The variations of superficial velocity lead to changes in the slug flow configuration. The variation has a greater impact on the Taylor bubble than the liquid slug. The changes in slug flow configuration result in differences in shear stress and mass transfer coefficient, leading to corresponding differences in electrochemical properties of AISI 316L stainless steel. [ABSTRACT FROM AUTHOR]

An accelerated erosion test with improved experimental efficiency is required to study the critical properties of pipe erosion failure in a reactor effluent air cooler used for the hydrocracking process. In this study, a single 90° elbow was simulated numerically with the design of an L16 orthogonal table to discuss the influencing factors of grid refinement at the bend. An analysis of the length–diameter ratio L1/D revealed that when L1/D increases to more than 5, the change in wall shear stress at the inner bend wall is insignificant. The mass transfer coefficient of ferrous ion and the maximum shear stress τm were also utilized to describe the erosion rate, including electrochemical corrosion and hydrodynamics. The factor that influenced mass transfer coefficient most was inlet velocity. The regions with high mass transfer coefficient were located at R1 and R2, with R1 showing a higher risk of electrochemical corrosion than R2. Operating pressure played a critical role in the effect on τm, which presented a low inside/high outside trend. The region with high τm was located at R3, where a high breakage risk of erodent product films was observed. [ABSTRACT FROM AUTHOR]

Dam tunnel ventilation has been widely used in underground hydropower station to save energy. In order to study the dam tunnel cooling (heating) effect, a 24 hours continuous field measurement is conducted in underground multi-tunnels; and heat transfer performance about the dam tunnel has been calculated and analyzed. Meanwhile, to figure out influencing factors to dam tunnel ventilation and heat transfer performance, based on similarity theory, a small-scale experimental set-up is made to simulate heat transfer process during air passing through the tunnel. The experimental results show that the velocity and temperature of the inlet air both have significant impacts on heat exchange. Taking the underground dam tunnel as a huge natural “air conditioner” to replace some mechanical heat/cold sources is an energy-saving method for Heating, Ventilation and Air Conditioning system in hydroelectric power plants. [ABSTRACT FROM AUTHOR]