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In order to address the issue of the difficulty in constructing maps from sensor‐acquired point clouds, a map construction algorithm is proposed for the effective conversion from sparse point clouds to dense point clouds. First, it constructs a dense point cloud map in real‐time using colour and depth information of keyframes. Then, it generates an accurate point cloud map by voxel filtering and coordinate conversion. Finally, the point cloud map is converted into an octree map using OctoMap. This article uses the TUM dataset for simulation analysis to verify the effectiveness of the algorithm. The results demonstrate that the algorithm can construct dense point cloud maps with high positioning accuracy in sparse point cloud scenarios. The algorithm improves the positioning accuracy by more than 15% under the fr1_xyz, fr1_room, fr1_desk2, fr1_desk1, fr2_desk and fr3_str_tex_near sequences, compared to ORB‐SLAM2, ORB‐SLAM3 and GX ORB‐SLAM2 algorithm [ABSTRACT FROM AUTHOR]

Diagnosing agricultural machinery faults is critical to agricultural automation, and identifying vibration signals from faulty bearings is important for agricultural machinery fault diagnosis and predictive maintenance. In recent years, data–driven methods based on deep learning have received much attention. Considering the roughness of the attention receptive fields in Vision Transformer and Swin Transformer, this paper proposes a Shift–Deformable Transformer (S–DT) network model with multi–attention fusion to achieve accurate diagnosis of composite faults. In this method, the vibration signal is first transformed into a time–frequency graph representation through continuous wavelet transform (CWT); secondly, dilated convolutional residual blocks and efficient attention for cross–spatial learning are used for low–level local feature enhancement. Then, the shift window and deformable attention are fused into S–D Attention, which has a more focused receptive field to learn global features accurately. Finally, the diagnosis result is obtained through the classifier. Experiments were conducted on self–collected datasets and public datasets. The results show that the proposed S–DT network performs excellently in all cases. With a slight decrease in the number of parameters, the validation accuracy improves by more than 2%, and the training network has a fast convergence period. This provides an effective solution for monitoring the efficient and stable operation of agricultural automation machinery and equipment. [ABSTRACT FROM AUTHOR]

Developing high−efficiency membrane materials for the rapid removal of organic dyes is crucial but remains a challenge. Polyoxometalates (POMs) clusters with anionic structures are promising candidates for the removal of cationic dyes via electrostatic interactions. However, their shortcomings, such as their solubility and inability to be mass−produced, hinder their application in water pollution treatment. Here, we propose a simple and green strategy utilizing the room temperature stirring method to mass produce nanoscale polyoxometalate−based metal−organic frameworks (POMOFs) with porous rhomboid−shaped dodecahedral and hexagonal prism structures. The products were labeled as POMOF1 (POMOF-PW12) and POMOF2 (POMOF-PMo12). Subsequently, a series of x wt% POMOF1/PAN (x = 0, 3, 5, and 10) nanofiber membranes (NFMs) were prepared using electrospinning technology, where polyacrylonitrile (PAN) acts as a "glue" molecule facilitating the bonding of POMOF1 nanoparticles. The as−prepared samples were comprehensively characterized and exhibited obvious water stability, as well as rapid selective adsorption filtration performance towards cationic dyes. The 5 wt% POMOF1/PAN NFM possessed the highest removal efficiency of 96.7% for RhB, 95.8% for MB, and 86.4% for CV dyes, which realized the selective separation over 95% of positively charged dyes from the mixed solution. The adsorption mechanism was explained using FT−IR, SEM, Zeta potential, and adsorption kinetics model, which proved that separation was determined via electrostatic interaction, hydrogen bonding, and π–π interactions. Moreover, the POMOF1/PAN membrane presented an outstanding recoverable and stable removal rate after four cycles. This study provides a new direction for the systematic design and manufacture of membrane separation materials with outstanding properties for contaminant removal. [ABSTRACT FROM AUTHOR]

The Micro-Electro-Mechanical System (MEMS) LiDAR point cloud in autonomous vehicles has a large deflection range, which results in slow registration speed and poor applicability. To maximize speed, an improved Normal Distribution Transform (NDT) method that integrates point cloud density features has been proposed. First, the point cloud is reduced using a modified voxel filter and a pass-through filter. Next, the Intrinsic Shape Signature (ISS) algorithm is utilized to analyze the point cloud features and extract key points; the Four-Point Congruent Set (4PCS) algorithm is then employed to calculate the initial pose under the constraints of the key point set to complete the coarse registration. Finally, the self-adaptive segmentation model is constructed by using a K-D tree to obtain the density features of key points, and the NDT algorithm is combined with this model to form an SSM-NDT algorithm, which is used for fine registration. Each algorithm was compared on the autonomous vehicle dataset PandaSet and actual collected datasets. The results show that the novel method increases the speed by at least 60% and takes into account good registration accuracy and strong anti-interference. [ABSTRACT FROM AUTHOR]

To reduce the pain and the probability of cross-infection caused by the invasive blood glucose testing instruments, the ex vivo glucose measurement is of high significance. The electrical property of blood varies with the density of the glucose, which can be sensed by measuring its reflected coefficient in millimeter-wave. In this article, we built a contactless glucose solution concentration measurement system based on 77-GHz FMCW radar. Several preliminary signal processing algorithms are cascaded with a deep neural network to improve the accuracy of glucose solution concentration measurement. Our experiment shows that the resolution of this ex vivo glucose measurement can achieve up to 0.1 mg/mL. [ABSTRACT FROM AUTHOR]

Teleost fish can synthesize one of the major omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs), docosahexaenoic acid (DHA, 22:6n-3), from dietary α-linolenic acid (ALA; 18:3n-3), via elongase of very long–chain fatty acid (Elovl) and fatty acid desaturase (Fads). However, it remains unclear which elongase is primarily responsible for the endogenous synthesis of DHA. Here, in this study, the knockout models of the two major elongases, Elovl2 and Elovl5, were generated by CRISPR/Cas9 approach in zebrafish and comparatively analyzed. The homozygous mutants were validated by Sanger sequencing, mutation-mediated PCR, and whole-mount in situ hybridization analysis of the endogenous target genes. Compared with wild-type (WT) counterparts, the content of DHA was significantly reduced by 67.1% (P < 0.05) in the adult liver and by 91.7% (P < 0.01) in the embryo at 3-day post-fertilization (dpf) of the elovl2 mutant, but not of the elovl5 mutant. Further study revealed that elovl2 and fads2 was upregulated by 9.9-fold (P < 0.01) and 9.7-fold (P < 0.01) in the elovl5 mutant, and elovl5 and fads2 were upregulated by 15.1-fold (P < 0.01) and 21.5-fold (P < 0.01) in the elovl2 mutant. Our study indicates that although both Elovl2 and Elovl5 have the elongase activity toward C20, the upregulation of elovl2 could completely replace the genetic depletion of elovl5, but upregulation of elovl5 could not compensate the endogenous deficiency of elovl2 in mediating DHA synthesis. In conclusion, the endogenous synthesis of DHA in is mediated by Elovl2 but not Elovl5 in zebrafish and a DHA-deficient genetic model of zebrafish has been generated. [ABSTRACT FROM AUTHOR]

Eucalyptol (1,8-cineole), the major constituent of eucalyptus oil (EO), was used in traditional medicine as a remedy for colds and bronchitis. This study aimed at clarifying the effect of eucalyptol on respiratory immune function of CD8 and CD4 cells, and alveolar macrophages (AM). Thirty male Sprague-Dawley rats were divided into experimental and control groups. The drug was given once a day for 3 weeks and the experimental group was divided according to the eucalyptol dose into: 30, 100, and 300 mg·kg-1 groups. Flow cytometry was used to detect the phagocytic function of CD4, CD8 cells, and AM in the bronchopulmonary lavage fluid. The 30 and 100 mg·kg-1 groups had an up-regulation effect on CD8 (p < 0.05), with no significant effect on macrophage phagocytosis. The 300 mg·kg-1 group had an inhibitory effect on CD8 and macrophage phagocytosis (p < 0.05), with no significant difference in CD4 between groups. Further investigation was conducted to evaluate the effect of EO on immune function in rats by detecting blood T, B, and NK cells using flow cytometry, and blood IgA, IgG, IgM, and IFN-γ levels by ELISA. High dosage of eucalyptol significantly reduced the proportion of blood B and NK cells (p < 0.05). IgA was decreased in the 100 and 300 mg·kg-1 groups (p < 0.05). There are no significant differences between the number of T cells and the IgG, IgM, and IFN-γ levels between experimental and control groups. Rational use of EO containing eucalyptol can improve the immune function of the respiratory tract and the body immunity, while high dose could have damaging effects, through modifying the phagocytic function of CD8 cells and reducing the proportion of blood B cells, NK cells, and IgA. [ABSTRACT FROM AUTHOR]

Per-recruit analyses, with consideration for uncertainty in growth, natural mortality and maturity, were conducted for European bream Abramis brama in the downstream section of the Irtysh River in China to assess its status. The Chapman-Robson method produced an estimate of total mortality rate (Z) of 0.65 year−1. The natural mortality rates (M) were estimated as 0.13 and 0.26 year−1, resulting in corresponding estimates of current fishing mortality rate (Fcur) of 0.52 and 0.39 year−1, respectively. All the estimates of yield per recruit (YPR), spawning stock biomass per recruit (SSB/R) and corresponding biological reference points (BRPs) were sensitive to M. The uncertainty of growth and maturity parameters had limited impacts on the estimates of BRPs, but had a large effect on the YPR and SSB/R outputs. Our findings indicate that A. brama may be at higher risk of growth overfishing than those of recruitment overfishing. In addition, increasing the tc to nine years might ensure that the spawning potential ratios (SPRs) are above the management targets under all ranges of F with comparatively small impacts on YPR regardless of M. In addition to providing a basic assessment for A. brama in the downstream of the Irtysh River in China, our study presents a comprehensive approach that may be useful for data-limited species in other fisheries. [ABSTRACT FROM AUTHOR]

Commercial application of nuclear genetic male sterility has been improved recently by a novel technique, Seed Production Technology (SPT), which incorporates transgenic maintainer lines capable of propagating non‐transgenic nuclear male‐sterile lines for use as female parents in hybrid production. Here, we identified a rice nuclear male‐sterile mutant, Oswbc11, with abnormal pollen development and lipid transport. We finely mapped the Oswbc11 gene into a 12.5‐kb region on chromosome 10 and found one candidate gene, which had a base substitution (C to T) resulting in a premature stop codon and was functionally confirmed by CRISPR/Cas9 technology. Gene OsWBC11 encodes a sub‐family member of adenosine triphosphate‐binding cassette transporter, which participates in the active transport of a wide range of molecules across membranes. Moreover, the agronomic traits of Oswbc11 mutants showed no significant differences compared to the wild‐type control except for the seed setting rate. These results indicated that Oswbc11 gene could be used in rice hybrid breeding as a recessive nuclear male‐sterile gene combined with CRISPR/Cas9 and the SPT technology and applied in different rice varieties. [ABSTRACT FROM AUTHOR]

The failure of resistance spot welding (RSW) joint will severely affect the deformation behaviours of sheet metal parts and it is crucial for vehicle safety to predict whether and when the RSW joints will fail in crash loading. The objective of this paper is to investigate the resultant-based failure criterion for RSW joint and to verify its applicability in crush simulation of structural components. The testing methods of the failure criterion were proposed and implemented for single-spot RSW joint. The failure parameters of tension, shear, bending and torsion were resolved from the testing result of single-spot RSW joint. Validation of the failure criterion was conducted through a crush test of a component consisting of multiple RSW joints. It was concluded that the proposed testing methods and the resultant-based failure criterion could reflect the spot welding performance and predict the failure of RSW joints in the crush simulation. [ABSTRACT FROM AUTHOR]

A series of meta-substituted fatty acid octaester derivatives and their transition-metal complexes of meso- tetraphenyl porphyrins (TPP-8OOCR, with R=C n−1H2 n−1, n=8, 12, or 16) have been prepared through very simple synthesis protocols. The thermotropic phase behavior and the liquid crystalline (LC) organization structures of the synthesized porphyrin derivatives were systematically investigated by a combination of differential scanning calorimetry (DSC), polarized optical microscopy (POM), and variable-temperature small-angle X-ray scattering/wide-angle X-ray scattering (SAXS/WAXS) techniques. The shorter octanoic acid ester substituted porphyrin (C8-TPP) did not show liquid crystallinity and its metal porphyrins exhibited an uncommon columnar mesophase. The lauric acid octaester (C12-TPP) and the palmitic acid octaester (C16-TPP) series porphyrins generated hexagonal columnar mesophase Colh. Moreover, the metal porphyrins C12-TPPM and C16-TPPM with M=Zn, Cu, or Ni, exhibited well-organized Colh mesophases of broad LC temperature ranges increasing in the order of TPPNih mesophase, the broadness of the discotic LC range, and the specific UV/Vis absorption and fluorescence emission behaviors make the symmetrically substituted fatty acid octaester porphyrins and their metal complexes very attractive for variant applications. [ABSTRACT FROM AUTHOR]

Focuses on a study which compared the adaptive Time-To-Live (TTL), polling-every-time and invalidation consistency approaches in relation to cache consistency in the World Wide Web. Importance of caching; Indepth look at the problem of cache consistency; Methodology used to conduct the study; Results of the study.

The decision in 2006 to abolish the agricultural tax, which had lasted for thousands of years, contributed to the prosperity of agriculture, and with it the growing importance of soil N2O emissions in China. However, most of the previous literature ignored soil N2O emissions due to their too small share in total agricultural greenhouse gas (GHG) emissions. This paper attempts to take soil N2O emissions as an important variable in the measurement of agricultural green total factor productivity (AGTFP), which incorporates environmental pollution into the analytical framework of agricultural production efficiency. Three impressive results were found. Firstly, soil N2O emissions play an increasingly important role in agricultural GHG emissions. The proportion of soil N2O emissions in agricultural GHG emissions increased from 4.52% in 1998 to 4.83% in 2006, and then to 5.36% in 2016. Secondly, the regional difference of soil N2O emissions in AGTFP is visible. In 2016, although soil N2O emissions accounted for a small proportion (about 5%) of the total agricultural GHG emissions in China, the AGTFP including soil N2O emissions was much lower than that excluding soil N2O emissions, especially in areas with high agricultural and population density. Finally, over time, soil N2O emissions have had an increasing effect on AGTFP. Compared with 1998–2006, the impact of excluding soil N2O emissions on AGTFP in 2007–2016 was more evident than that including soil N2O emissions. [ABSTRACT FROM AUTHOR]

As reported, previous studies ofPhoxinus phoxinus ujmonensis(Cypriniformes: Cyprinidae) have focused primarily on morphology and ecology. In this study, we cloned and sequenced the complete nucleotide sequence of the mitochondrial genome forP. phoxinus ujmonensis. The mitogenome was 17,738 bp in length, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The overall base composition of the heavy strain was 28.50% for A, 28.24% for T, 25.32% for C and 17.94% for G. The control region was revealed to contain tandem repeats. The mitogenome data ofP. phoxinus ujmonensisshould contribute to phylogenetic analysis and studies of population genetics ofPhoxinusfishes. [ABSTRACT FROM AUTHOR]

In this study, we determined the complete nucleotide sequence of the mitochondrial genome for a cold water fish,Leuciscus idus. The complete mitochondrial genome was sequenced and analyzed using the primer walking method and 30 pairs of newly designed primers were used. Direct sequencing of the PCR products demonstrated that the genome contained the same 37 mitochondrial genes (two ribosomal RNA, 22 transfer RNA and 13 protein-coding genes) and two main non-coding regions (the control region and the origin of the light strand replication) as those found in other vertebrates. Nearly all the protein-coding genes’ start codons were ATG exceptCOX 1, meanwhile, the termination codons of which varied with TAA, TA, T, or TAG. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome ofLeuciscus leuciscus baicalensiswas cloned and sequenced in the present study. The genome which had a mostly conserved structural organization in comparison with that of other teleost fish was 16,606 bp in size. It consisted of 37 genes (13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes), and 2 main non-coding regions (the control region and the origin of the light strand replication). All protein-coding genes started with ATG except forCOX 1, which began with GTG. However, the termination codons of 13 protein-coding genes varied with TAA, TA, T or TAG. The complete mitochondrial genome sequence provided useful information for phylogenetic analysis and studies of population genetics ofL. leuciscus baicalensis. [ABSTRACT FROM PUBLISHER]