132 research outputs found
The Research of Product Graphical Information Sharing Technology of Virtual Manufacturing Enterprise in E-Commerce Environment
This paper has built a product model by UML and corresponding Product Schema. Then we have illuminated transmit mechanism of the product information by a dumbbell XML document. At last, we have pointed out the direction of the research. This research will provide a significative explore to the product data interchange between the members of virtual manufacturing enterprise in e-commerce environmen
CAM/CAD Point Cloud Part Segmentation via Few-Shot Learning
3D part segmentation is an essential step in advanced CAM/CAD workflow.
Precise 3D segmentation contributes to lower defective rate of work-pieces
produced by the manufacturing equipment (such as computer controlled CNCs),
thereby improving work efficiency and attaining the attendant economic
benefits. A large class of existing works on 3D model segmentation are mostly
based on fully-supervised learning, which trains the AI models with large,
annotated datasets. However, the disadvantage is that the resulting models from
the fully-supervised learning methodology are highly reliant on the
completeness of the available dataset, and its generalization ability is
relatively poor to new unknown segmentation types (i.e. further additional
novel classes). In this work, we propose and develop a noteworthy few-shot
learning-based approach for effective part segmentation in CAM/CAD; and this is
designed to significantly enhance its generalization ability and flexibly adapt
to new segmentation tasks by using only relatively rather few samples. As a
result, it not only reduces the requirements for the usually unattainable and
exhaustive completeness of supervision datasets, but also improves the
flexibility for real-world applications. As further improvement and innovation,
we additionally adopt the transform net and the center loss block in the
network. These characteristics serve to improve the comprehension for 3D
features of the various possible instances of the whole work-piece and ensure
the close distribution of the same class in feature space.Comment: 7 pages, 5 figure
Mendelian randomization analysis revealed a gut microbiota–mammary axis in breast cancer
BackgroundObservational epidemiological studies suggested an association between the gut microbiota and breast cancer, but it remains unclear whether the gut microbiota causally influences the risk of breast cancer. We employed two-sample Mendelian randomization (MR) analysis to investigate this association.MethodsWe used summary statistics of the gut microbiome from a genome-wide association study (GWAS) of 18,340 individuals in the MiBioGen study. GWAS summary statistics for overall breast cancer risk and hormone receptor subtype-specific analyses were obtained from the UK Biobank and FinnGen databases, totaling 400,000 individuals. The inverse variance-weighted (IVW) MR method was used to examine the causal relationship between the gut microbiome and breast cancer and its subtypes. Sensitivity analyses were conducted using maximum likelihood, MR-Egger, and MR pleiotropic residual sums and outliers methods.ResultsThe IVW estimates indicated that an increased abundance of Genus_Sellimonas is causally associated with an increased risk of ER+ breast cancer [odds ratio (OR) = 1.09, p = 1.72E−04, false discovery rate (FDR) = 0.02], whereas an increased abundance of Genus_Adlercreutzia was protective against ER+ breast cancer (OR = 0.88, p = 6.62E−04, FDR = 0.04). For Her2+ breast cancer, an increased abundance of Genus_Ruminococcus2 was associated with a decreased risk (OR = 0.77, p = 4.91E−04, FDR = 0.04), whereas an increased abundance of Genus_Erysipelatoclostridium was associated with an increased risk (OR = 1.25, p = 6.58E−04, FDR = 0.04). No evidence of heterogeneity or horizontal pleiotropy was found.ConclusionOur study revealed a gut microbiota–mammary axis, providing important data supporting the potential use of the gut microbiome as a candidate target for breast cancer prevention, diagnosis, and treatment
Hepatoprotective Effect of Polyphenol-Enriched Fraction from Folium Microcos
Folium Microcos (FM), the leaves of Microcos paniculata L., shows various biological functions including antioxidant activity and α-glucosidase inhibitory effect. However, its therapeutic potential in acute liver injury is still unknown. This study investigated the hepatoprotective effect and underlying mechanisms of the polyphenol-enriched fraction (FMF) from Folium Microcos. FMF exhibited strong free radical scavenging activities and prevented HepG2/Hepa1–6 cells from hydrogen peroxide- (H2O2-) induced ROS production and apoptosis in vitro. Antioxidant activity and cytoprotective effects were further verified by alleviating APAP-induced hepatotoxicity in mice. Western blot analysis revealed that FMF pretreatment significantly abrogated APAP-mediated phosphorylation of MAPKs, activation of proapoptotic protein caspase-3/9 and Bax, and restored expression of antiapoptotic protein Bcl2. APAP-intoxicated mice pretreated with FMF showed increased nuclear accumulation of nuclear factor erythroid 2-related factor (Nrf2) and elevated hepatic expression of its target genes, NAD(P)H:quinine oxidoreductase 1 (NQO1) and hemeoxygenase-1(HO-1). HPLC analysis revealed the four predominantly phenolic compounds present in FMF: narcissin, isorhamnetin-3-O-β-D-glucoside, isovitexin, and vitexin. Consequently, these findings indicate that FMF possesses a hepatoprotective effect against APAP-induced hepatotoxicity mainly through dual modification of ROS/MAPKs/apoptosis axis and Nrf2-mediated antioxidant response, which may be attributed to the strong antioxidant activity of phenolic components
Maternal bisphenols exposure and thyroid function in children: a systematic review and meta-analysis
BackgroundEvidence from animal experiments and epidemiological studies has reported controversial results about the effects of prenatal bisphenols (BPs) exposure on childhood thyroid function. This study aims to explore the associations of prenatal exposure to BPs with thyroid-related hormones (THs) in newborns and early childhood, with a particular focus on the sex-dependent and exposure level effects.MethodsCorrelated studies were systematically searched from PubMed, Web of Science, Medline, Cochrane, and Embase until February 21, 2024. The exposures assessed include bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), bisphenol AF (BPAF), and tetrachlorobisphenol A (TCBPA). THs measured were thyroid stimulating hormone (TSH), total tri-iodothyronine (TT3), total thyroxine (TT4), free tri-iothyronine (FT3), and free thyroxine (FT4). Effect estimates were quantified using coefficients from multivariable regression models. Statistical analyses were completed using Stata 16.0. The methodological quality of the included studies was evaluated using the Newcastle-Ottawa Scale (NOS).ResultsEleven cohort studies comprising 5,363 children were included in our meta-analysis. Prenatal bisphenol concentrations were statistically significant related to alterations in thyroid hormones in children, exclusively in female offspring, including reduced TSH (β = -0.020, 95% CI: -0.036, -0.005) and increased TT3 levels (β = 0.011, 95% CI: 0.001, 0.021), and exposure to high concentration of bisphenols (>1.5 ug/g creatinine) significantly reduced FT3 levels in children (β = -0.011, 95% CI: -0.020, -0.003).ConclusionPrenatal bisphenol exposure is linked to alterations in thyroid hormone levels in girls, necessitating enhanced measures to control bisphenol exposure levels during pregnancy for child health protection.Systematic Review Registrationhttps://inplasy.com, identifier INPLASY202450129
Simultaneous Mutations in Multi-Viral Proteins Are Required for Soybean mosaic virus to Gain Virulence on Soybean Genotypes Carrying Different R Genes
BACKGROUND: Genetic resistance is the most effective and sustainable approach to the control of plant pathogens that are a major constraint to agriculture worldwide. In soybean, three dominant R genes, i.e., Rsv1, Rsv3 and Rsv4, have been identified and deployed against Soybean mosaic virus (SMV) with strain-specificities. Molecular identification of virulent determinants of SMV on these resistance genes will provide essential information for the proper utilization of these resistance genes to protect soybean against SMV, and advance knowledge of virus-host interactions in general. METHODOLOGY/PRINCIPAL FINDINGS: To study the gain and loss of SMV virulence on all the three resistance loci, SMV strains G7 and two G2 isolates L and LRB were used as parental viruses. SMV chimeras and mutants were created by partial genome swapping and point mutagenesis and then assessed for virulence on soybean cultivars PI96983 (Rsv1), L-29 (Rsv3), V94-5152 (Rsv4) and Williams 82 (rsv). It was found that P3 played an essential role in virulence determination on all three resistance loci and CI was required for virulence on Rsv1- and Rsv3-genotype soybeans. In addition, essential mutations in HC-Pro were also required for the gain of virulence on Rsv1-genotype soybean. To our best knowledge, this is the first report that CI and P3 are involved in virulence on Rsv1- and Rsv3-mediated resistance, respectively. CONCLUSIONS/SIGNIFICANCE: Multiple viral proteins, i.e., HC-Pro, P3 and CI, are involved in virulence on the three resistance loci and simultaneous mutations at essential positions of different viral proteins are required for an avirulent SMV strain to gain virulence on all three resistance loci. The likelihood of such mutations occurring naturally and concurrently on multiple viral proteins is low. Thus, incorporation of all three resistance genes in a soybean cultivar through gene pyramiding may provide durable resistance to SMV
Design and Experimental Validation of a Rapidly Deployable Folding Floating Bridge Based on Rigid-Flexible Combination
As a temporary means of water transportation, floating bridges play an important role in the military and other fields. However, traditional floating bridges have limitations such as large size, heavy weight, and slow construction time. In this paper, we propose a rigid-flexible composite folding floating bridge. The main structure of the floating bridge consists of three layers: the bridge deck, airbag, and water bag. The floating bridge units are connected by flexible connectors to allow for pre-connection and folding of the bridge, reducing storage and transportation space, and improving construction efficiency. The proposed floating bridge also has a complete engineering application design and has been checked for safety and reliability (including the strength, buoyancy, and bearing capacity of the connections). We used AQWA software to simulate and analyze the anchorage scheme of the floating bridge and its response to wave loads and conducted a ballast test on a floating bridge model to verify its feasibility as a main bearing body. The results show that the floating bridge we designed has the advantages of being lightweight, having fewer consumables, having a small storage and transportation space, and being able to be constructed quickly
Research progress and challenges faced by unmanned aerial vehicles in complex underground spaces
The technological development and application status of underground complex space UAVs are analyzed. It is pointed out that underground complex space UAVs face problems such as insufficient individual performance, limited environmental situational awareness and autonomous navigation capabilities, and limited formation collaboration capabilities. In order to solve the above problems, the development trends of key technologies for underground UAVs are prospected. â‘ Small and lightweight integrated UAV design technology is proposed. By improving the mechanical structure of the UAV, improving the integration of information perception sensors such as LiDAR and depth camera with control systems, and optimizing power management systems, the ultimate goal is to improve the cruise speed, endurance time, and other performance of individual UAV. â‘¡ Situation awareness and autonomous navigation technology in GPS rejection environment is proposed. The key technical challenges such as simultaneous localization and mapping (SLAM) navigation and real-time path planning should be overcome. The limitations of algorithms around specific scenarios should be gradually broken through. The perception capability, environmental adaptability, and robustness of unmanned systems should be improved. â‘¢ Formation collaboration control technology under limited information is proposed. The technical problems such as heterogeneous/isomorphic UAV cluster collaboration, and wireless communication in complex channel environments should be overcome. By optimizing UAV swarm intelligence control strategies, information interaction mechanisms, and task decision-making collaboration mechanisms, the robustness of clustered unmanned systems should be enhanced. The adaptability of unmanned systems in complex underground environments should be improved. Furthermore, the task execution efficiency and success rate of unmanned systems should be improved
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