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This study used Kinect V2 sensor to collect the three-dimensional point cloud data of banana pseudostem and developed an automatic measurement method of banana pseudostem width. The banana plant was selected as the research object in a banana plantation in Fusui, Guangxi. The mobile measurement of banana pseudostem was carried out at a distance of 1 m from the banana plant using the field operation platform with Kinect V2 as the collection equipment. To eliminate the background data and improve the processing speed, a cascade classifier was used to recognize banana pseudostems from the depth image, extract the region of interest (ROI), and transform the ROI into a color point cloud combined with the color image; secondly, the point cloud was sparse by down-sampling; then, the point cloud noise was removed according to the classification of large-scale and small-scale noise; finally, the stem point cloud was segmented along the y-axis, and the difference between the maximum and minimum values in the x-axis direction of each segment was calculated as its horizontal width. The center point of each segment point cloud was used to fit the slope of the stem centerline, and the average horizontal width was corrected to the stem diameter. The test results show that the average measurement error is only 2.7 mm, the average relative error was 1.34%, and the measurement time is only about 300 ms. It could provide an effective solution for the automatic and rapid measurement of stem width of banana plants and other similar plants.

In this article, a robust distributed fault detection and isolation (FDI) scheme for second-order multiagent systems (MASs) with exogenous disturbances based on partial agents' absolute state will be proposed. We design a robust control law with disturbance rejection term for each agent, then, an augmented MAS closed-loop system without disturbance term is formed. We construct a bank of observers for FDI in some selected agents for the augmented MAS closed-loop system based on the idea of an unknown input observer (UIO), where the observers for FDI of the entire MAS are updated by the selected agents' absolute states and relative states between themselves and their neighbors, which avoids utilizing all agents' absolute states. We run observers for FDI in the selected agents to generate residuals to detect the faulty agent between themselves and their neighbors. Meanwhile, the existence proof of observers for FDI is also presented. It is worth noting that the remaining healthy agents will reach consensus again under the original robust control law if the communication topology is still connected. Finally, the effectiveness of the proposed scheme is illustrated by a multivehicle example.

Assessment of sphingosine-1-phosphate receptor 1 (S1PR1) expression could be a unique tool to determine the neuroinflammatory status for central nervous system (CNS) disorders. Our preclinical results indicate that PET imaging with [(11)C]CS1P1 radiotracer can quantitatively measure S1PR1 expression changes in different animal models of inflammatory diseases. Here we developed a multiple step F-18 labeling strategy to synthesize the radiotracer [(18)F]FS1P1, sharing the same structure with [(11)C]CS1P1. We explored a wide range of reaction conditions for the nucleophilic radiofluorination starting with the key ortho-nitrobenzaldehyde precursor 10. The tertiary amine additive TMEDA proved crucial to achieve high radiochemical yield of ortho-[(18)F]fluorobenzaldehyde [(18)F]12 starting with a small amount of precursor. Based on [(18)F]12, a further four-step modification was applied in one-pot to generate the target radiotracer [(18)F]FS1P1 with 30∼50% radiochemical yield, >95% chemical and radiochemical purity, and a high molar activity (37∼166.5 GBq/μmol, decay corrected to end of synthesis, EOS). Subsequently, tissue distribution of [(18)F]FS1P1 showed a high brain uptake (ID%/g) of 0.48 ± 0.06 at 5 min, and bone uptake of 0.27 ± 0.03, 0.11 ± 0.02 at 5, and 120 min respectively, suggesting no in vivo defluorination. MicroPET studies showed [(18)F]FS1P1 has high macaque brain uptake with a standard uptake value (SUV) of ~2.3 at 120 min. Radiometabolite analysis in nonhuman primate plasma samples indicated that [(18)F]FS1P1 has good metabolic stability, and no major radiometabolite confounded PET measurements of S1PR1 in nonhuman primate brain. Overall, [(18)F]FS1P1 is a promising F-18 S1PR1 radiotracer worthy of further clinical investigation for human use.

This study aimed to investigate the relationships between LPCAT1 expression and clinicopathologic parameters of hepatocellular carcinoma (HCC), further, to explore the effect of LPCAT1 on overall survival (OS) in patients with HCC, and its possible mechanism. Bioinformatics analysis using high throughput RNA-sequencing data from TCGA was utilized to explore the differential expression of LPCAT1 between normal and tumor tissues, and the associations between LPCAT1 expression and clinicopathological parameters. Survival analyses and subgroup survival analyses were utilized to elucidate the effect of LPCAT1 on OS in patients with HCC. Univariate analysis and multivariate analysis were used to investigate the prognostic factors. Potential LPCAT1 related tumor genes were identified by the methodology of differentially expressed genes (DEGs) screening. GO term enrichment analysis, KEGG pathway analysis and the PPI network were used to explore the potential mechanism. LPCAT1 was significantly overexpressed in HCC tumor tissues compared with normal tissues. The LPCAT1 expression was related to tumor grade, ECOG score, AFP and TNM stage, with p values of 0.000, 0.000, 0.007 and 0.000, respectively. Multivariate analysis demonstrated that LPCAT1 expression was independently associated with OS, with an HR of 1.04 (CI: 1.01–1.06, p = 0.003). The KEGG pathway enrichment analyses showed that overlapped DEGs mainly participate in the cell cycle. Finally, we identified a hub gene, CDK1, which has been reported to act on the cell cycle, consistent with the result of KEGG enrichment analysis. Collectively, these data confirmed LPCAT1 was upregulated in HCC, and was an independent predictor of the prognosis.

Magnetic materials with ingeniously designed structures may be utilized as highly efficient microwave absorbing materials (MAMs) working at ultralow matching thicknesses. However, it remains a challenge to decrease the matching thickness by synergistically tailoring the composition and structure of magnetic MAMs. In this work, a series of magnetic MAMs have been synthesized by sequentially annealing Fe-bdc nanorods in air and hydrogen. The results show that with the increase in hydrogen reduction temperature, the Fe

Purpose: Alpine wetland ecosystems can contribute large amounts of methane (CH 4) to the atmosphere; however, their emissions vary with environmental conditions. Microbial activity is known to drive CH 4 emissions, but how environmental conditions determine microbial activity is still uncertain. Here, we seek to quantify the variability of the CH 4 flux, to detect the effects of CH 4-related microbes on CH 4 emissions, and to study the dependency of these effects on environmental conditions. Materials and methods: We measured the CH 4 flux, environmental conditions, and CH 4-related microbial communities (mcrA and pmoA gene abundances for methanogens and methanotrophs, respectively) under three hydrological conditions (submerged, soil–water interface, and emerged) from seven sampling sites in the Zoige alpine wetland, China. Results and discussion: The CH 4 flux varied greatly from 0 to 41 mg m −2 h −1 in the Zoige alpine wetland. The methanogenic and methanotrophic abundances both showed positive correlations with CH 4 flux, while CH 4 flux increased linearly with the increase of soil water content (SWC) when SWC was above 60%. CH 4 flux and methanogenic and methanotrophic abundances maintained the high levels when soil C:N ratio was in the range of 11–24 and decreased exponentially with the increase of soil DOC:TN ratio in Zoige alpine wetland, which might result from its influence on nutrient supply for microbial decomposition process. Conclusion: The results provided new insight into the effects of CH 4-related microbes on CH 4 emission and its response to different environmental conditions and helped us to comprehend the risks of high CH 4 emissions from alpine wetlands under climatic change and anthropogenic disturbance.

Regulating phase composition and dispersion state of oxide particles inside metal-organic frameworks-derived carbon composite holds enormous potential in enhancing dielectric property and microwave absorption performance. Herein, solid state reaction between Fe-bdc nanorod and TiO2 shell has been used to synthesize a series of Fe-Ti oxides/carbon (FTO/C) composites at different annealing temperatures. The results show that with the increase of temperature, the grain size of oxide particles, which tend to distribute in the center of carbon rod, has increased, resulting in the formation of continuous conductive surface caron layer. Meanwhile, the aspect ratio of carbon rod would decrease, which would hinder the construction of conductive path in paraffin matrix. At lower temperature, internal oxide particles are less crystallized (Fe2.5Ti0.5)1.04O4, which may induce obvious dipole polarization. While at higher temperature, phase conversion from (Fe2.5Ti0.5)1.04O4 to Fe2TiO4 and FeTiO3 would bring about more interfaces, which generate strong interfacial polarization. Therefore, dielectric loss of as-prepared FTO/C composites would be enhanced with rising temperature until 700 oC, and impedance matching condition would always be improved with increasing temperature, in terms of lowest matching thickness in whole Ku or X bands. Consequently, S-700 owns a broad effective absorption bandwidth (EAB) of 6.84 GHz at 2.2 mm, covering whole Ku band and S-800 owns a large EAB of 4.16 GHz at 2.8 mm, covering whole X band. This work may provide novel insights into the design of metal-organic frameworks-derived carbon composite with desired dielectric properties through controlling the composition and dispersion of inner oxide particles.