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Tracked inspection robots have demonstrated their versatility in a wide range of applications. However, challenges arising from issues such as skidding and slipping have posed obstacles to achieving precise and efficient trajectory control. This paper introduces a method to determine the steering parameters of robot based on the surrounding obstacles and road information. The primary objective is to enhance the steering efficiency of tracked robots. The corresponding relationship between the track speed, driving force and track steering radius of the tracked robot is obtained. Considering the influence of track skid and slip, relationship models about the steering radius and traveling speed of the robot are established. The minimum and maximum steering radii in the obstacle avoidance process are analyzed, and a mathematical model of the relationship between the steering angle of the robot and the distance between the side obstacles is established. The trajectory deviation model of the tracked robot is established, and a principle analysis of the LiDAR ranging is completed. This lays the foundation for a steering measurement and control system for tracked robots. ADAMS(2020) software is used to establish the multi-body dynamics model of the tracked robot, and three different obstacle-avoiding steering control strategies are designed for the robot in a simulated environment with space obstacles. The simulation experiment demonstrates that the robot achieves more efficient obstacle avoidance steering through the use of differential steering, leading to a decrease in both track skid and slip rates. Through the simulation experiment, it can be seen that the robot uses differential steering to complete the obstacle avoidance steering movement more efficiently, and the track skid and slip rates are smaller. The simulation results are used to complete the steering control experiment of the tracked robot on different road surfaces. The results show that by adjusting the track driving parameters, the robot can effectively complete the obstacle-avoiding steering movement by using the differential steering control strategy, which verifies the accuracy of the steering control strategy. [ABSTRACT FROM AUTHOR]

Like other abiotic stresses, salt stress has become a major factor that restricts the growth, distribution and yield of crops. Research has shown that increasing the nitrogen content in soil can improve the salt tolerance of plants and nitrate transporter (NRT) is the primary nitrogen transporter in plants. Suaeda salsa (L.) Pall is a strong halophyte that can grow normally at a salt concentration of 200 mM. The salt stress transcriptome database of S. salsa was found to contain four putative genes that were homologous to NRT, including SsNRT1.1A, SsNRT1.1B, SsNRT1.1C and SsNRT1.1D. The cDNA of SsNRT1.1s was predicted to contain open reading frames of 1791, 1782, 1755 and 1746 bp, respectively. Sequence alignment and structural analysis showed that the SsNRT1.1 amino acids were inducible by salt and have conserved MFS and PTR2 domains. Subcellular localization showed they are on the endoplasmic reticulum. Overexpression of SsNRT1.1 genes in transgenic Arabidopsis improves its salt tolerance and SsNRT1.1C was more effective than others. We constructed a salt-stressed yeast cDNA library and used yeast two-hybrid and BiFC technology to find out that SsHINT1 and SsNRT1.1C have a protein interaction relationship. Overexpression of SsHINT1 in transgenic Arabidopsis also improves salt tolerance and the expressions of Na+ and K+ were increased and reduced, respectively. But the K+/Liratio was up-regulated 11.1-fold compared with the wild type. Thus, these results provide evidence that SsNRT1.1C through protein interactions with SsHINT1 increases the K+/Na+ ratio to improve salt tolerance and this signaling may be controlled by the salt overly sensitive (SOS) pathway. [ABSTRACT FROM AUTHOR]

Image sampling is a fundamental technique for image compression, which greatly improves the efficiency of image storage, transmission, and applications. However, existing sampling algorithms primarily consider human visual perception and discard irrelevant information based on subjective preferences. Unfortunately, these methods may not adequately meet the demands of computer vision tasks and can even lead to redundancy because of the different preferences between human and computer. To tackle this issue, this paper investigates the key features of computer vision. Based on our findings, we propose an image sampling method based on the dominant color component (ISDCC). In this method, we utilize a grayscale image to preserve the essential structural information for computer vision. Then, we construct a concise color feature map based on the dominant channel of pixels. This approach provides relevant color information for computer vision tasks. We conducted experimental evaluations using well-known benchmark datasets. The results demonstrate that ISDCC adapts effectively to computer vision requirements, significantly reducing the amount of data needed. Furthermore, our method has a minimal impact on the performance of mainstream computer vision algorithms across various tasks. Compared to other sampling approaches, our proposed method exhibits clear advantages by achieving superior results with less data usage. [ABSTRACT FROM AUTHOR]

With the rapid progress of artificial intelligence, various perception networks were constructed to enable Internet of Things (IoT) applications, thereby imposing formidable challenges to communication bandwidth and information security. Memristors, which exhibit powerful analog computing capabilities, emerged as a promising solution expected to address these challenges by enabling the development of the next-generation high-speed digital compressed sensing (CS) technologies for edge computing. However, the mechanisms and fundamental properties of memristors for achieving CS remain unclear, and the underlying principles for selecting different implementation methods based on various application scenarios have yet to be elucidated. A comprehensive overview of memristor-based CS techniques is currently lacking. In this article, we systematically presented CS requirements on device performance and hardware implementation. The relevant models were analyzed and discussed from the mechanism level to elaborate the memristor CS system scientifically. In addition, the method of deploying CS hardware using the powerful signal processing capabilities and unique performance of memristors was further reviewed. Subsequently, the potential of memristors in all-in-one compression and encryption was anticipated. Finally, existing challenges and future outlooks for memristor-based CS systems were discussed. [ABSTRACT FROM AUTHOR]

Both ZeBrafish (ZB), a recently identified DNA transposon in the zebrafish genome, and SB, a reconstructed transposon originally discovered in several fish species, are known to exhibit high transposition activity in vertebrate cells. Although a similar structural organization was observed for ZB and SB transposons, the evolutionary profiles of their homologs in various species remain unknown. In the present study, we compared their taxonomic ranges, structural arrangements, sequence identities, evolution dynamics, and horizontal transfer occurrences in vertebrates. In total, 629 ZB and 366 SB homologs were obtained and classified into four distinct clades, named ZB, ZB-like, SB, and SB-like. They displayed narrow taxonomic distributions in eukaryotes, and were mostly found in vertebrates, Actinopterygii in particular tended to be the major reservoir hosts of these transposons. Similar structural features and high sequence identities were observed for transposons and transposase, notably homologous to the SB and ZB elements. The genomic sequences that flank the ZB and SB transposons in the genomes revealed highly conserved integration profiles with strong preferential integration into AT repeats. Both SB and ZB transposons experienced horizontal transfer (HT) events, which were most common in Actinopterygii. Our current study helps to increase our understanding of the evolutionary properties and histories of SB and ZB transposon families in animals. [ABSTRACT FROM AUTHOR]

Tracked inspection robots possess prominent advantages in dealing with severe environment rescue, safety inspection, and other important tasks, and have been used widely. However, tracked robots are affected by skidding and slipping, so it is difficult to achieve accurate control. For example, the control parameters of a tracked robot are the same during driving, but the pressure, shear force and steering resistance of the robot on the road surface are different, which affects the steering characteristics of the robot on complex terrain. Based on analysis of the structural parameters and steering radius of the robot, the traction force and resistance torque models of the tracked robot were established, and the plane dynamics of the robot's steering were analyzed and solved. The corresponding relationships between the road parameters, relative steering radius, and lateral relative offset of the robot on three typical roads were obtained. Mathematical models of the robot's track speed and relative steering radius with and without skid and slip were established. Through simulation analysis of Matlab software, the corresponding relationship between the relative steering radius of the robot and the velocity difference of the two tracks were obtained. Taking angular obstacles as an example, three obstacle-avoidance steering control strategies, once turning in situ center, twice turning in situ center, and large-radius steering were developed. The tracked robot and obstacle multi-body dynamic simulation models were constructed using ADAMS simulation software. The simulation results show that all three methods can complete the steering tasks according to the requirements; however, under the influence of skid and slip, the trajectory of the robot deviates from the ideal trajectory, which has a great impact on large-radius steering, even though the large-radius obstacle-avoidance steering control strategy has the advantages of a smooth trajectory, fast steering speed, and high efficiency. The obstacle-avoidance steering experiments were completed by the robot prototype, which verifies the rationality of robot steering theory, which could provide the corresponding theoretical basis for autonomous obstacle-avoidance navigation control of a tracked robot. [ABSTRACT FROM AUTHOR]

Simple Summary: Despite the discovery of the Tigger family of pogo transposons in the mammalian genome, the evolution profile of this family is still incomplete. Here, we conducted a systematic evolution analysis for Tigger in nature. The data revealed that Tigger was found in a broad variety of animals, and extensive invasion of Tigger was observed in mammal genomes. Common horizontal transfer events of Tigger elements were observed across different lineages of animals, including mammals, that may have led to their widespread distribution, while parasites and invasive species may have promoted Tigger HT events. Our results also indicate that the activity of Tigger transposons tends to be low in vertebrates; only one mammalian genome and fish genome may harbor active Tigger. The data of this study revealed that Tigger was found in a wide variety of animal genomes, including 180 species from 36 orders of invertebrates and 145 species from 29 orders of vertebrates. An extensive invasion of Tigger was observed in mammals, with a high copy number. Almost 61% of those species contain more than 50 copies of Tigger; however, 46% harbor intact Tigger elements, although the number of these intact elements is very low. Common HT events of Tigger elements were discovered across different lineages of animals, including mammals, that may have led to their widespread distribution, whereas Helogale parvula and arthropods may have aided Tigger HT incidences. The activity of Tigger seems to be low in the kingdom of animals, most copies were truncated in the mammal genomes and lost their transposition activity, and Tigger transposons only display signs of recent and current activities in a few species of animals. The findings suggest that the Tigger family is important in structuring mammal genomes. [ABSTRACT FROM AUTHOR]

Simple Summary: Transposable elements, including DNA transposons, play a significant role in genetic material exchanges between prokaryotes and eukaryotes. Comparative profiling of the evolution pattern of DNA transposons between prokaryotes and eukaryotes may identify potential genetic material exchanges between them and provide insights into the evolutionary history of prokaryotic and eukaryotic genomes. The members of the IS630-Tc1-mariner (ITm) group may represent the most diverse and widely distributed DNA transposons in nature, and the discovery of new members of this group is highly expected based on the increasing availability of genome sequencing data. We discovered a new superfamily (termed Sailor) belonging to the ITm hyperfamily, which differed from the known superfamilies of Tc1/mariner, DDxD/pogo and DD34E/Gambol, regarding phylogenetic position and catalytic domain. Our data revealed that Sailor was distributed in both prokaryotes and eukaryotes and suggested that horizontal transfer (HT) events of Sailor may occur from prokaryotic to eukaryotic genomes. Finally, internal transmissions of Sailor in prokaryotes and eukaryotes were also detected. Here, a new superfamily of IS630-Tc1-mariner (ITm) DNA transposons, termed Sailor, is identified, that is characterized by a DD82E catalytic domain and is distinct from all previously known superfamilies of the ITm group. Phylogenetic analyses revealed that Sailor forms a monophyletic clade with a more intimate link to the clades of Tc1/mariner and DD34E/Gambol. Sailor was detected in both prokaryotes and eukaryotes and invaded a total of 256 species across six kingdoms. Sailor is present in nine species of bacteria, two species of plantae, four species of protozoa, 23 species of Chromista, 12 species of Fungi and 206 species of animals. Moreover, Sailor is extensively distributed in invertebrates (a total of 206 species from six phyla) but is absent in vertebrates. Sailor transposons are 1.38–6.98 kb in total length and encoded transposases of ~676 aa flanked by TIRs with lengths between 18, 1362 and 4 bp (TATA) target-site duplications. Furthermore, our analysis provided strong evidence of Sailor transmissions from prokaryotes to eukaryotes and internal transmissions in both. These data update the classification of the ITm group and will contribute to the understanding of the evolution of ITm transposons and that of their hosts. [ABSTRACT FROM AUTHOR]

Simple Summary: In the class of insects, bees are advanced evolutionary groups that play a pivotal role in ecosystem balance, agriculture, and food security. Transposons are the driving factors of genome evolution and speciation, which shape the genomes of almost all organisms. Among them, the Tc1/mariner and pogo superfamily, as the most widely distributed transposons in nature, are widely reported in insects. However, in bees, the research on transposons has never been systematically reported. Therefore, this study focuses on annotating the transposons of the Tc1/mariner and pogo superfamily of bees that were sequenced, revealing the distribution, diversity, potential activities, evolutionary patterns, and structural characteristics of transposons in different bees. Bees (Apoidea), the largest and most crucial radiation of pollinators, play a vital role in the ecosystem balance. Transposons are widely distributed in nature and are important drivers of species diversity. However, transposons are rarely reported in important pollinators such as bees. Here, we surveyed 37 bee genomesin Apoidea, annotated the pogo and Tc1/mariner transposons in the genome of each species, and performed a phylogenetic analysis and determined their overall distribution. The pogo and Tc1/mariner families showed high diversity and low abundance in the 37 species, and their proportion was significantly higher in solitary bees than in social bees. DD34D/mariner was found to be distributed in almost all species and was found in Apis mellifera, Apis mellifera carnica, Apis mellifera caucasia, and Apis mellifera mellifera, and Euglossa dilemma may still be active. Using horizontal transfer analysis, we found that DD29-30D/Tigger may have experienced horizontal transfer (HT) events. The current study displayed the evolution profiles (including diversity, activity, and abundance) of the pogo and Tc1/mariner transposons across 37 species of Apoidea. Our data revealed their contributions to the genomic variations across these species and facilitated in understanding of the genome evolution of this lineage. [ABSTRACT FROM AUTHOR]

Most of the existing models of structural life prediction in early carbonized environment are based on accelerated erosion after standard 28 days of cement-based materials, while cement-based materials in actual engineering are often exposed to air too early. These result in large predictions of the life expectancy of mineral-admixture cement-based materials under early CO2-erosion and affecting the safe use of structures. To this end, different types of mineral doped cement-based material test pieces are formed, and early CO2-erosion experimental tests are carried out. On the basis of the analysis of the existing model, the influence coefficient of CO2-erosion of the mineral admixture Km is introduced, the relevant function is given, and the life prediction model of the mineral admixture cement-based material under the early CO2-erosion is established and the model parameters are determined by using the particle group algorithm (PSO). It has good engineering applicability and guiding significance. [ABSTRACT FROM AUTHOR]

Gold catalysts have been reported to exhibit good performance in aerobic oxidation of alcohols, but the intrinsic origin of the catalytic reactivity is still illusive. The catalyst preparation method, the morphology of the gold particles, and even the support might be key factors that determine the activity. Here, we prepared a series of gold catalysts with different supports, i.e., the hydrotalcite (HT), ZnO, MgO, Al2O3, and SiO2, by using the atomically controlled Au25 nanoclusters (NCs) as the gold precursor. The characterization results of the X-ray diffraction (XRD), UV-vis and transmission electron microscopy (TEM) show that the gold particles were mostly uniformly distributed on the supports, with a mean particle size within 3 nm. In aerobic oxidation of benzyl alcohol, the MgAl-HT- and Al2O3-supported Au25 NCs display good performances, with turnover frequency (TOF) values of ~2927 and 2892 h−1, respectively, whereas the SiO2-, MgO-, and ZnO-supported analogues show much inferior activity. The high resolution TEM and X-ray photoelectron spectra (XPS) results suggest that the interactions between gold and the supports in different samples are differing, which influences the morphology and the nature of gold. Our results further point to the importance of acid-base property of the support and the metal-support synergy rather than the gold particle size alone in achieving high-performance in selective alcohol oxidation. Moreover, this work provided a good way to design gold catalysts with controllable sizes that is crucial for understanding the reaction process in aerobic oxidation of alcohol. [ABSTRACT FROM AUTHOR]

Adsorption and activation for substrates and the stability of Pd species in Pd-based catalysts are imperative for their wider adoption in industrial and practical applications. However, the influence factor of these aspects has remained unclear. This indicates a need to understand the various perceptions of the structure–function relationship that exists between microstructure and catalytic performance. Herein, we revisit the catalytic performance of supported-ionic-liquid-phase stabilized Pd-based catalysts with nitrogen-containing ligands as a promoter for acetylene hydrochlorination, and try to figure out their regulation. We found that the absolute value of the differential energy, |Eads(C2H2)-Eads(HCl)|, is negative correlated with the stability of palladium catalysts. These findings imply that the optimization of the electron structure provides a new strategy for designing highly active yet durable Pd-based catalysts. [ABSTRACT FROM AUTHOR]

Although transposon-mediated enhancer trapping (ET) is successfully applied in diverse models, the efficiency of various transposon systems varies significantly, and little information is available regarding efficiency of enhancer trapping by various transposons in zebrafish. Most potential enhancers (Ens) still lack evidence of actual En activity. Here, we compared the differences in ET efficiency between sleeping beauty (SB), piggyBac (PB) and Tol2 transposons. Tol2 represented the highest germline transfer efficiencies at 55.56% (NF0 = 165), followed by SB (38.36%, NF0 = 151) and PB (32.65%, NF0 = 149). ET lines generated by the Tol2 transposon tended to produce offspring with a single expression pattern per line, while PB and SB tended to generate embryos with multiple expression patterns. In our tests, 10 putative Ens (En1–10) were identified by splinkerette PCR and comparative genomic analysis. Combining the GFP expression profiles and mRNA expression patterns revealed that En1 and En2 may be involved in regulation of the expression of dlx1a and dlx2a, while En6 may be involved in regulation of the expression of line TK4 transgene and rps26, and En7 may be involved in the regulation of the expression of wnt1 and wnt10b. Most identified Ens were found to be transcribed in zebrafish embryos, and their regulatory function may involve eRNAs. [ABSTRACT FROM AUTHOR]