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As a common vegetable variety, asparagus is rich in B vitamins, vitamin A, and trace elements such as folate, selenium, iron, manganese, and zinc. With the increasing market demand, China has become the world's largest cultivated area for asparagus production and product exportation. However, traditional asparagus grading mostly relies on manual visual judgment and needs a lot of manpower input to carry out the classification operation, which cannot meet the needs of large-scale production. To address the high labor cost and labor-intensive production process resulting from the large amount of manpower input and low accuracy of existing asparagus grading devices, this study proposed an improved asparagus grading system and method based on TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) objective evaluation and SVM (support vector machine) prediction. The key structure of classification device was analyzed first, the key components were designed, and the structural parameters were determined by theoretical calculation. Through analysis of the factors affecting asparagus quality, three key attributes were determined: length, diameter, and bruises, which were used as reference attributes to conduct experimental analysis. Then, the graded control groups were set up, combining the TOPSIS principle with weighting, and a score for each asparagus sample was determined. These scores were compared with those of a graded control group to derive the grade of each asparagus, and these subsets of the dataset were used as the training set and the test set, excluding the error caused by the subjectivity of the manual judgment. Based on a comparison of the accuracies of different machine learning models, the support vector machine (SVM) was determined to be the most accurate, and four SVM methods were used to evaluate the test set: linear SVM, quadratic SVM, cubic SVM, and medium Gaussian SVM. The test results showed that the grading device was feasible for asparagus. The bruises had a large influence on asparagus quality. The training accuracy of the medium Gaussian SVM method was high (96%), whereas its test accuracy was low (86.67%). The training accuracies and test accuracy of the quadratic and cubic SVM methods were 93.34%. The quadratic SVM and cubic SVM were demonstrated to have better generalization ability than the medium Gaussian SVM method for predicting unknown grades of asparagus and meeting the operational requirements of the asparagus grading. [ABSTRACT FROM AUTHOR]

In this paper, a patch array antenna with wideband circular polarization and high gain is proposed by utilizing a hybrid metasurface (MS). A corner-cut slotted patch antenna was chosen as the source due to the possible generation of CP mode. The hybrid MS (HMS), consisting of a receiver MS (RMS) arranged in a 2 × 2 array of squared patches and a linear-to-circular polarization conversion (LCPC) MS surrounding it was then utilized as the superstrate driven by the source. The LCPC MS cell is a squared-corner-cut patch with a 45° oblique slot etched, which has the capability for wideband LCPC. The LCPC unit cell possesses wideband PC capabilities, as demonstrated by the surface current analysis and S-parameter simulations conducted using a Floquet–port setup. The LP EM wave radiated by the source antenna was initially received by the RMS, then converted to a CP wave as it passed through the LCPC MS, and ultimately propagated into space. To further enhance the LCPC properties, an improved HMS (IHMS) was then proposed with four cells cut at the corners, based on the original HMS design. To verify this design, both CMA and E-field were utilized to analyze the three MSs, indicating that the IHMS possessed a wideband LCPC capability compared to the other two MSs. The proposed antenna was then arranged in a 2 × 2 array with sequential rotation to further enhance its properties. As demonstrated by the measurements, the array antenna achieved an S11 bandwidth of 60.5%, a 3 dB AR bandwidth of 2.85 GHz, and a peak gain of 15.1 dBic, all while maintaining a low profile of only 0.09λ0. [ABSTRACT FROM AUTHOR]

(1) Background: Diabetes is a common metabolic disease that seriously endangers human health. In the present study, we investigated the therapeutic effects of the active ingredient Eleutheroside B (EB) from the traditional Chinese medicine Eleutheroside on diabetes mellitus in a zebrafish model. Concomitant hepatic injury was also analysed, along with the study of possible molecular mechanisms using metabolomics technology. This work should provide some theoretical references for future experimental studies. (2) Methods: A zebrafish diabetes model was constructed by soaking in a 1.75% glucose solution and feeding a high-fat diet. The intervention drug groups were metformin (100 μg∙mL−1) and EB (50, 100, and 150 μg∙mL−1) via water-soluble exposure for 30 days. Glucose, TG, TC, LDL-C, and HDL-C were evaluated in different treatment groups. GLUT4 protein expression was also evaluated in each group, and liver injury was observed by HE staining. Metabolomics techniques were used to investigate the mechanism by which EB regulates endogenous markers and metabolic pathways during the development of diabetes. (3) Results: All EB treatment groups in diabetic zebrafish showed significantly reduced body mass index (BMI) and improved blood glucose and lipid profiles. EB was found to upregulate GLUT4 protein expression and ameliorate the liver injury caused by diabetes. Metabolomics studies showed that EB causes changes in the metabolic profile of diabetic zebrafish. These were related to the regulation of purine metabolism, cytochrome P450, caffeine metabolism, arginine and proline metabolism, the mTOR signalling pathway, insulin resistance, and glycerophospholipid metabolism. (4) Conclusions: EB has a hypoglycaemic effect in diabetic zebrafish as well as significantly improving disorders of glycolipid metabolism. The mechanism of action of EB may involve regulation of the mTOR signalling pathway, purine metabolism, caffeine metabolism, and glycerophospholipid metabolism. [ABSTRACT FROM AUTHOR]

Recently, the application of cryogenic hoses in the field of cryogenic media has become a hot topic, especially in the industry of offshore liquefied natural gas and aerospace field. However, the structure of cryogenic hoses is complex, and reasonable structural properties are required due to the harsh working conditions. There is still plenty of scope for further development to improve the performance in all aspects. In this paper, the current development status of cryogenic hoses for liquefied natural gas (LNG) transportation is reviewed first, including the types, manufacturers, structural forms, performance, and key technical challenges. And then, the recent progress and prospect of cryogenic hoses for cryogenic liquid transportation (such as LNG and liquid oxygen) are summarized, including structure design, low-temperature resistant polymers, liquid oxygen compatible polymers, and leakage monitoring technologies. This paper provides a comprehensive overview of the research development and application of cryogenic hoses. Moreover, future research directions have been proposed to facilitate its practical applications in aerospace. [ABSTRACT FROM AUTHOR]

Regeneration has been considered as an ideal way for the post-treatment of waste FCC catalyst (ECat). In this work, the degeneration mechanism of ECat was firstly researched and attributed to the increasing of strong acid sites accessibility of ECat in contrast with fresh FCC catalyst by adsorption FTIR. Based on the proposed degeneration mechanism, ECat was successfully regenerated through suitable weakening for strong acid sites by boron modification. Characterization and evaluation results suggested that, the strong acid sites of regenerated ECat (R-ECat) were apparently decreased by boron modification which had significantly improve the heavy oil catalytic cracking performance of R-ECat. Because of the excellent performance, R-ECat in this work could successfully substitute for partial fresh FCC catalyst in FCC unit, which would provide a practicable way for the reutilization of ECat. [ABSTRACT FROM AUTHOR]

In this work, squeeze casting experiments of flywheel housing components with a large wall thickness difference and a complex shape were carried out with AlSi9Mg aluminum alloy. The defects, microstructures, and mechanical properties under different process parameters were investigated. Furthermore, the local pressurization process was applied to the thick-walled positions to force-feed the cast defects. The mechanical properties and microstructures at these positions were analyzed. The results showed that the surface quality of formed components was good and that local pressurization could effectively reduce the shrinkage cavity and shrinkage porosity in thick walls, but the scope and effect of forced feeding were limited. The optimum process parameters were a pouring temperature of 650 °C, a specific pressure of 48 MPa, a mold temperature of 220 °C, a local pressurization of 800 MPa, and pressure delay times of 15 s (side A) and 17 s (side B). The ultimate tensile strength, yield strength, and elongation of the formed component under validation experiments of the optimum process parameters were 201 MPa, 103 MPa, and 5.1%. Meanwhile, the fine grains of primary α-Al were mainly rosette and equiaxed grains, and the average grain size was about 40 μm. The microstructure of the eutectic silicon was acicular and was prone to segregation under pressure. According to profile morphology, the positions after pressurization were divided into a deformation zone, a direct action zone, and an indirect action zone. The coexistence of as-cast and plastic deformation microstructures was observed. The effect of local pressurization mainly involved a change in the solidification process, plastic deformation, and forced feeding. [ABSTRACT FROM AUTHOR]

The census and management of hazard-bearing entities, along with the integrity of data quality, form crucial foundations for disaster risk assessment and zoning. By addressing the challenge of feature confusion, prevalent in single remotely sensed image recognition methods, this paper introduces a novel method, Spatially Constrained Deep Learning (SCDL), that combines deep learning with spatial constraint strategies for the extraction of disaster-bearing bodies, focusing on dams as a typical example. The methodology involves the creation of a dam dataset using a database of dams, followed by the training of YOLOv5, Varifocal Net, Faster R-CNN, and Cascade R-CNN models. These models are trained separately, and highly confidential dam location information is extracted through parameter thresholding. Furthermore, three spatial constraint strategies are employed to mitigate the impact of other factors, particularly confusing features, in the background region. To assess the method's applicability and efficiency, Qinghai Province serves as the experimental area, with dam images from the Google Earth Pro database used as validation samples. The experimental results demonstrate that the recognition accuracy of SCDL reaches 94.73%, effectively addressing interference from background factors. Notably, the proposed method identifies six dams not recorded in the GOODD database, while also detecting six dams in the database that were previously unrecorded. Additionally, four dams misdirected in the database are corrected, contributing to the enhancement and supplementation of the global dam geo-reference database and providing robust support for disaster risk assessment. In conclusion, leveraging open geographic data products, the comprehensive framework presented in this paper, encompassing deep learning target detection technology and spatial constraint strategies, enables more efficient and accurate intelligent retrieval of disaster-bearing bodies, specifically dams. The findings offer valuable insights and inspiration for future advancements in related fields. [ABSTRACT FROM AUTHOR]

The physical properties of Ti6Al4V powder affect the spreadability of the powder and uniformity of the powder bed, which had a great impact on the performance of built parts made by powder bed fusion technology. Micro-computed tomography is a well-established technique used to analyze the non-destructivity of the objects' interior. Ti6Al4V powders were scanned with micro-CT to show the internal and external information of all the particles. The morphology, particle size distribution, hollow particle ratio, density, inclusion, and specific surface area of the powder samples were quantitatively characterized, and the relationship of flowability with these physical properties was analyzed in this work. The research results of this article showed that micro-CT is an effective way to characterize these items, and can be developed as a standard method of powder physical properties in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates the functional adaptation and underlying molecular mechanisms of hemoglobins (Hbs) in the two species of Eremias lizards dwelling on the Qinghai-Tibet Plateau. By measuring O2 equilibrium curves of purified Hbs at different pH and temperature in the absence and presence of ATP and/or Cl−, the study found that the high-altitude populations of the two species of Eremias lizards exhibit convergent high Hb-O2 affinity compared to the respective lowland counterparts while demonstrating distinct ATP-mediated allosteric regulation. Hbs of the highland E. argus showed high ATP sensitivity and ATP-dependent strong Bohr effect compared to E. multiocellata. The underlying mechanisms of these functional variations may be attributed to the varying β2/β1 globin ratios, combined with substitutions on the β2-type globin, as suggested by Hb isoform identification and structural analysis of tetrameric Hbs. In addition, Hbs of these Eremias lizards have similarly low temperature sensitivities and relatively high Bohr effects at lower temperatures, which could minimize the impact of temperature fluctuations on Hb-O2 affinity and facilitate the release of O2 in the cold extremities at low temperatures. The functional adaptation and underlying molecular mechanisms of hemoglobins (Hbs) have primarily concentrated on mammals and birds, with few reports on reptiles. This study aimed to investigate the convergent and species-specific high-altitude adaptation mechanisms of Hbs in two Eremias lizards from the Qinghai-Tibet Plateau. The Hbs of high-altitude E. argus and E. multiocellata were characterized by significantly high overall and intrinsic Hb-O2 affinity compared to their low-altitude populations. Despite the similarly low Cl− sensitivities, the Hbs of high-altitude E. argus exhibited higher ATP sensitivity and ATP-dependent Bohr effects than that of E. multiocellata, which could facilitate O2 unloading in respiring tissues. Eremias lizards Hbs exhibited similarly low temperature sensitivities and relatively high Bohr effects at lower temperatures, which could help to stably deliver and release O2 to cold extremities at low temperatures. The oxygenation properties of Hbs in high-altitude populations might be attributed to varying ratios of β2/β1 globin and substitutions on the β2-type globin. Notably, the Asn12Ala in lowland E. argus could cause localized destabilization of the E-helix in the tetrameric Hb by elimination of hydrogen bonds, thereby resulting in its lowest O2 affinity. This study provides a valuable reference for the high-altitude adaptation mechanisms of hemoglobins in reptiles. [ABSTRACT FROM AUTHOR]

This paper presents a practical and straightforward control strategy for robotic manipulators with unknown dynamics to achieve prescribed tracking performance, which has implementation advantages compared with previous work. In particular, an improved extended state observer (ESO) synthesized with a continuously differentiable friction model and time-varying gains is presented to estimate system states and unknown dynamics. This ESO outperforms the conventional ones in dealing with friction mutations while avoiding peaking estimation values in the initial stage. By combining the prescribed performance function and the proposed ESO, an independent joint control scheme is proposed for a robotic manipulator to keep the tracking error within a predefined performance bound based only on position measurements. The effectiveness of the proposed control scheme is verified by comparative simulation and experimental results on a six-degrees-of-freedom robotic manipulator with active disturbance rejection controller and PID methods. [ABSTRACT FROM AUTHOR]

Cellulose crystallinity is a crucial factor influencing stem strength and, consequently, wheat lodging. However, the genetic dissection of cellulose crystallinity is less reported due to the difficulty of its measurement. In this study, VIS/NIR spectra and cellulose crystallinity were measured for a wheat accession panel with diverse genetic backgrounds. We developed a reliable VIS/NIR model for cellulose crystallinity with a high determination coefficient (R2) (0.95) and residual prediction deviation (RPD) (4.04), enabling the rapid screening of wheat samples. A GWAS of the cellulose crystallinity in 326 wheat accessions revealed 14 significant SNPs and 13 QTLs. Two candidate genes, TraesCS4B03G0029800 and TraesCS5B03G1085500, were identified. In summary, this study establishes an efficient method for the measurement of cellulose crystallinity in wheat stems and provides a genetic basis for enhancing lodging resistance in wheat. [ABSTRACT FROM AUTHOR]