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In order to explore the dynamic changes and stage specificity of metabolites in bamboo shoots during its growth, widely targeted metabolomics based on ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used to analyze fresh bamboo shoots harvested at heights of 10 and 25 cm. The results showed that a total of 875 metabolites belonging to 13 categories were identified from bamboo shoots, including sugars, alcohols and flavonoids, whose relative contents significantly increased in 25 cm-high bamboo shoots. Moreover, the results of multivariate statistical analyses showed that the metabolites in bamboo shoots had an obvious stage specificity. Totally 283 significantly differential metabolites were identified between the two growth stages, of which 102 metabolites were annotated to 82 metabolic pathways. The contents of 20 major nutrients did not significantly differ between the two growth stages; however, the contents of metabolites related to taste, flavor and bioactive function were higher, while the content of bitter compounds was lower in the 25 cm-high bamboo shoots. Therefore, compared with the 10 cm-high bamboo shoots, the 25 cm-high bamboo shoots have a higher comprehensive economic value and are more suitable for harvesting. The results of this study can provide a theoretical reference for the comprehensive development and sustainable utilization of Chimonobambusa tumidissinoda.

Utilizing natural balsa wood as the raw material, cellulose was prepared using microwave-assisted chlorocholine chloride/lactic acid deep eutectic solvents (DES) in synergy with H2O2, followed by further preparation of cellulose nanocrystals (CNCs) via ultrasound treatment. Initially, the optimal process for balsa wood cellulose preparation was explored through single-factor and response surface experiments involving microwave-assisted DES in synergy with H2O2 treatment. Subsequently, cellulose nanocrystals were prepared using ultrasound, and the resulting materials were characterized and analyzed for their chemical composition, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), nanoparticle size distribution, transmission electron microscopy (TEM) analysis, and thermogravimetric-differential scanning calorimetry (TG-DSC). The results indicate that the yield of cellulose after microwave-assisted DES in synergy with H2O2 treatment can reach 42.96%. Furthermore, the cellulose nanocrystals obtained after ultrasound treatment exhibit a particle size ranging from 10 to 20 nm, with an average length of 515.9 nm, a crystallinity of 86.72%, and demonstrate good dispersion and thermal stability. Highlights: Microwave-assisted deep eutectic solvent (MaDES) is able to effectively remove lignin and hemicellulose from balsa wood. Determining optimal MaDES treatment conditions through response surface analysis. MaDES cellulose exhibits high cellulose purity with H2O2 treatment. Cellulose nanocrystals prepared from MaDES cellulose purified with H2O2 exhibit high aspect ratio and high crystallinity. Preparation of Cellulose Nanocrystals from Balsa wood Using MaDES with H2O2 treatment produces high-value cellulose nanocrystals while being environmentally friendly and sustainable. [ABSTRACT FROM AUTHOR]

In this study, it is considered that the question of adaptive tracking control of nonlinear systems containing unknown time‐varying parameters. To optimize the control effect, a fixed‐time control strategy is adopted, in which the upper bound of the settling time is connected with the designed parameters, but not to the initial conditions. In the design, the unknown time‐varying parameters are treated as the multiplication of known and unknown vectors, and the adaptive laws are constructed to estimate the mean value of the components in the unknown ones, which availably solve the difficulty of unknown control gains. Besides, the application of command filtered technique, which combined with the compensation signals containing the adaptive parameters, effectively avoids the "complexity explosion" problem. Further, Lyapunov stability theory verifies that the tracking error can always be kept within the boundaries of the performance functions, and converges to a designated neighbourhood of the origin within a fixed time, beyond that all signals of the closed‐loop system are bounded. Finally, the simulation results prove the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Chondroblastoma is one of the uncommon benign bone tumors, particularly when located in the mandibular condyle. Such a location makes its diagnosis difficult when based on only its clinical presentation and radiographic features. Herein the current report presents a case of chondroblastoma of the mandibular condyle: its clinical presentation, radiographic features, and immediate condylar reconstruction after resection. Additionally, the relevant literature is discussed to provide clinical recommendations for its diagnosis and treatment. Chondroblastoma has been reported so infrequently in the temporomandibular joint (TMJ), more common entities should first be considered in the differential diagnosis of masses in this location. Osteochondroma is the most frequent bone neoplasm in the TMJ. Since a correct diagnosis is difficult, additional tools, such as magnetic resonance imaging (MRI) and immunohistochemical analyses, should be used for diagnostics and surgical planning.