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The accumulated errors in multi-station measurements make it challenging to meet higher precision requirements for annular or straight tunnel measurements in the accelerator alignment field. In this paper, a study on fixing positions and orientations of laser trackers during the bundle adjustment is presented. First, we adopt the mixed least squares-total least squares algorithm to calculate the spatial-transformation parameters. Then, according to the principle of bundle adjustment based on laser trackers, we design four schemes and compare them to determine which scheme results in the highest precision. Experimental results show that fixing each station's position and orientation can considerably decrease the absolute point errors from 0.130 to 0.069 mm within 15 m × 10 m × 3 m, and fixing stations' orientations is better than fixing their positions. This research can derive high-precision schemes that effectively reduce accumulated errors in annular or straight tunnel measurements, and it can apply to other robotic sensors as well. [ABSTRACT FROM AUTHOR]

The biodiversity of peritrich ciliates from brackish biotopes is rarely investigated, especially members of the genus Pseudovorticella. Here, the morphology of three species of Pseudovorticella, i.e. P. cf. vestita (Stokes, 1883) Jankowski, 1976, P. spathulata sp. n., and P. qinghaiensis sp. n. isolated from brackish waters were studied. Pseudovorticella cf. vestita is characterized by inverted bell‐shaped cell; a J‐shaped macronucleus; a single contractile vacuole ventrally located; P3 three‐rowed; pellicle striated with highly developed pellicular vesicles; 18–22 transverse silverlines between peristome and aboral trochal band, and 9–13 between aboral trochal band and scopula. Pseudovorticella spathulata sp. n. differs from its congeners by the following combination of characters: elongate‐elliptical cell; a single contractile vacuole near ventral wall of infundibulum; a J‐shaped macronucleus; P3 three‐rowed; 24–34 silverlines between oral area and aboral trochal band and 6–10 between aboral trochal band and scopula. Pseudovorticella qinghaiensis sp. n. is characterized by: cell with an oval outline; a single contractile vacuole near ventral wall of infundibulum; a C‐shaped macronucleus; P3 three‐rowed; 30–35 and 9–11 transverse silverlines above and below the trochal band, respectively. The SSU rDNA sequences of five Pseudovorticella species, namely P. annulata, P. monilata, P. parakenti, P. spathulata sp. n., and P. cf. vestita, plus that of Zoothamnium hartwigi, are reported for the first time and their evolutionary relationships are investigated. Five undefined Pseudovorticella forms are considered might be conspecific with P. monilata. Two congeners are conspecific with P. spathulata sp. n. Phylogenetic analyses based on SSU rDNA sequences reveal that Pseudovorticella is not monophyletic and Z. hartwigi clusters with its congeners as expected. [ABSTRACT FROM AUTHOR]

Activated hepatic stellate cells (HSCs) are the main extracellular matrix (ECM)-producing cells in the injured liver and the key mediators of liver fibrosis; they also promote the progression of hepatocellular carcinoma (HCC). In the acidic extracellular microenvironment of HCC, HSCs are activated to promote the migration of HCC cells. It is worth attempting to alter the weak acidic microenvironment to promote activated HSC apoptosis to treat liver fibrosis and liver cancer. In the present study, a series of novel OA-amino acids analogues were designed and synthesized to introduce different amino acids in the 3-hydroxyl of OA using the ester condensation reaction to enhance hydrophilicity, alkalinity, and biological activity. We found that OA-lysine derivative (3g) could improve the hydrophilic of OA and induce HSCs apoptosis via inducing MMP depolarization and increasing intracellular Ca2+ levels. Additionally, 3g displayed a better hepatoprotective effect than OA (20 mg/kg, intragastric administration) against the acute liver injury induced by carbon tetrachloride (CCl4) in mice. The results suggested that basic amino acids (lysine) could effectively enhance OA’s hydrophilicity, alkalinity, and hepatoprotective activity in vitro and in vivo, which might be likely associated with increasing bioavailability and altering an extracellular weak acidic microenvironment with further verification. Therefore, the OA-lysine derivative (3g) has the potential to be developed as an agent with hepatoprotective activity. [ABSTRACT FROM AUTHOR]

Improper irrigation by Panax notoginseng growers can lead to soil consolidation, low fertilizer utilization, and decreased yield quality. In an attempt to provide a scientific and theoretical basis for Panax notoginseng cultivation to improve soil microhabitat and yield quality, field experiment were conducted on three-year-old Panax notoginseng in 2019, 2020, and 2021. The experimental design consisted of two control factors, the amount of irrigation (W) and the amount of fertilizer (F) applied. The irrigation was set to three levels, as W1, W2, and W3, with exact irrigation volumes of 5 mm, 10 mm, and 15 mm. The amount of fertilizer applied was different in all four growth stages. The amount of fertilizer applied according to the four growth stages (rooting stage: seedling stage: flowering stage: fruiting stage), where F1 (360–360–360–360 kg∙hm−2), F2 (288–360–432–360 kg∙hm−2), F3 (216–432–432–360 kg∙hm−2) and F4 (144–576–288–432 kg∙hm−2). The W and F were randomly combined to form a total of 12 treatments. And a control treatment (CK), was added, and CK was neither irrigated nor fertilization. For obtaining the best treatment results, the TOPSIS method was used to comprehensively evaluate the soil microbial biomass carbon and nitrogen, enzyme activity, physiological growth and saponin content of Panax notoginseng in 13 different water and fertilizer treatments. The results indicated that microbial biomass carbon and nitrogen, urease, sucrase, acid phosphatase and catalase activities of Panax notoginseng soil were significantly different (P < 0.05) and varied with the growth stage. The comprehensive evaluation by the TOPSIS method ranked W3F4 first and was the optimal treatment. The W3F4 treatment was more beneficial to the quality of Panax notoginseng than the other 12 treatments. W3F4 had the largest soil microbial biomass carbon and nitrogen content. W3F4 had the highest urease, sucrase, acid phosphatase, and catalase activities, which were 1.95, 1.69, 2.32, and 1.47 times higher than the CK treatment, respectively. W3F4 significantly improved R 1 , Rg 1 , Re, Rb 1 , and Rd saponin content. This study provided a theoretical basis for the water and fertilizer regulation of Panax notoginseng with its green, healthy and efficient quality cultivation. • W3F4 treatment was most beneficial for the increase of ginsenoside content. • Soil microbial biomass C and N were negatively associated with Re, and were positively associated with R 1. • Soil water content, sucrase, acid phosphatase, catalase, and urease were negatively correlated with Rb 1. [ABSTRACT FROM AUTHOR]

The reverse electrodialysis (RED) is a potential technique to harvest osmotic energy caused by different salinities. Owing to the negative surface-charged controlling effects of nanofluidic channel in 2D membrane, the power density has been achieved with high energy conversion efficiency for cations (Na+ with the counterpart of Cl−). However, anion-selective nanofluidic channel is rare but still required for promising application of RED due to its high higher diffusion rate resulting in desirable osmotic power energy. In this work, we constructed a two-dimensional layered MXene membrane with positive charge via amination strategy of 3-aminopropyltriethoxysilane (APTES) toward anion selectivity for efficient osmotic power harvesting. The power density of the resultant membrane can achieve a maximum of 10.98 W m−2 at a natural salinity gradient, higher than the commercial benchmark of 5 W m−2. Under regulating environmental conditions including operation temperatures, pH and the existence of pollutants (heavy metal ions and organic pollution) of the simulated electrolyte solution, a higher power density of 20.66 W m−2 can be reached through Cl− transmembrane transport. During 10-h testing, the attenuation of output power density was just 3%. The applicable stability still maintains under the contaminative environment of heavy metal ions or organic pollution. These results will bring an innovative design of anion-selective membrane for osmotic energy conversion and widen the practical application in ion selectivity. [Display omitted] • The anion-selective nanofluidic channel is constructed to obtain desirable osmotic power energy. • Amination strategy can effectively reverse the surface charge of MXene membrane. • The output power of 10.98 W m−2 can be achieved at 50-fold salinity gradient of Cl−. [ABSTRACT FROM AUTHOR]