Xingyi Normal University for Nationalities

We developed a dual-functional fluorescent probe based on cerium-doped carbon dots (Ce-CDs). The Ce-CDs were synthesized via a facile hydrothermal route using trimesic acid, L-lysine, and cerium nitrate as precursors, serving to quantify both tetracycline (TET) and carmine (CM). The Ce-CDs show excellent excitation-independent fluorescence, with optimal excitation at 340nm, emission at 410nm, and quantum yield of 17.4%. Due to the inner filter effect and static quenching, their fluorescence intensity decreased linearly with increasing TET/CM concentration, enabling a new fluorescent probe. The developed sensing platform exhibited a wide linear response (0.125-50.0 µM) and high sensitivity, with limits of detection of 0.037 µM for TET and 0.035 µM for CM. The method's accuracy and precision were rigorously evaluated in complex food samples. Recoveries for TET in a variety of meats (pork, pork liver, beef, chicken) fell between 94.4% and 113%, and for CM in foodstuffs (dried strawberries, bayberry juice, red bull drink) fell between 92.0% and 115%, with relative standard deviations ≤ 5.8%. Thus, Ce-CDs are excellent probes for food TET and CM detection.

The rapid, sensitive, and cost-effective detection of tannic acid (TA) in complex food matrices is essential for improving food safety standards. To meet this demand, nitrogen-doped carbon quantum dots (N-CDs) were prepared using a one-pot hydrothermal reaction using L-malic acid, citric acid, and tris(2-aminoethyl) amine as precursors. The excitation wavelength of the N-CDs was 430 nm, and the emission wavelength was 490 nm. Transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD) were used to characterize the prepared N-CDs, and the results revealed a uniform morphology and a nitrogen-rich surface structure. In addition, we found that the N-CDs exhibited excellent selectivity for TA, primarily attributed to the fluorescence quenching effect of TA on the N-CDs. Therefore, a fluorescent sensor for TA detection was constructed based on the N-CDs, with a linear detection range of 0.500-250 µM (R2 = 0.99987) and a detection limit of 0.15 µM (S/N = 3). The practical applicability of the sensor was demonstrated by analyzing TA in beer, red wine, and apple juice, achieving recoveries ranging from 101% to 116% and RSDs between 3.0% and 5.4%. The fluorescence assay results were closely related to the HPLC-DAD validation results, highlighting the accuracy of the method. The N-CDs-based detection platform offers the advantages of simplicity, sensitivity, and reliability, providing a promising tool for routine TA monitoring in food safety applications.

The polynomial curve fitting models are among the most common trend extrapolation prediction models. The time‐independent variable can take on various values during model construction, and it is a theoretical question whether different value selections will affect the model’s structure. This study proves that when the time‐independent variable t is sampled equidistantly, the least‐squares error (SSE) of the established polynomial curve fitting model remains constant, the model validation F ‐statistic is equal, and the polynomial degree of the model is consistent. The demonstration that equidistant sampling of the time‐independent variable maintains structural stability in the model will provide theoretical support for the modeling and application of this model.

Mode multiplexing, which transmits parallel data information via orthogonal light field modes, has attracted extensive research attention in on-chip high-capacity optical communication. To reduce the device footprint, a mode multiplexer with sub-wavelength pixelated superstructures is proposed. However, due to the accumulation of device fabrication deviation, the communication performance of mode multiplexer will be deteriorated. Herein, we propose a pixelated superstructure duty cycle optimization strategy to decrease the number of cylindrical air holes, which can mitigate the cumulative disturbance of fabrication deviation. The duty cycle of pixelated superstructure is adjusted by eliminating pixels below the specified Figure of Merit threshold, achieving an improvement from 20.6% to 13.9%. Based on this, we optimize a three-mode multiplexer (TE0, TE1, TE2) and demonstrate a mode multiplexing communication by transmitting 72 Gbit/s QPSK-OFDM signals. The experimental results show that the insertion loss of the fabricated three-mode multiplexer reduces by approximately 1.9 dB ∼ 2.8 dB compared with the direct binary search scheme, and the communication sensitivity is optimized about 1.5 dB at the center wavelength of 1550 nm. Our proposed pixelated superstructure duty cycle optimization strategy performs the pixel updating or random mutation by means of roulette method, increasing the randomness of value search during algorithm execution, which will prevent the target value from falling into a local optimal solution. This work is expected to promote the development of on-chip mode multiplexing and provide what we believe to be new technological paths for high-capacity optical communications.

Abstract The circumscription is an elegant non-monotonic logic. However, computing circumscription remains challenging due to its computational complexity. This paper presents a weighted partial Maximum Satisfiability (MaxSAT) encoding approach that addresses circumscription, allowing us to leverage state-of-the-art MaxSAT solvers for efficient computation.This approach introduces a linear-time encoding scheme that captures both parallel and prioritized circumscription without requiring fresh predicates. Furthermore, we develop a systematic model enumeration strategy using blocking clauses, which enables the complete and efficient enumeration of circumscription models while avoiding redundancy.Extensive experiments have been conducted on benchmarks such as model-based circuit diagnostics, random and industrial SAT problems, and extended stable marriage problems. The results indicate that our MaxSAT-based implementation, circ-maxsat, achieves comparable performance with state-of-the-art methods such as circ2dlp and aspino. Notably, circ-maxsat outperforms other solvers on the (extended) stable marriage problem in terms of computational efficiency. This study advances the computation of circumscription and introduces new applications of MaxSAT in non-monotonic reasoning.

Background: Rock climbing is a comprehensive sport that integrates physical strength, coordination, and psychological resilience. Significant differences may exist in the psychological states and biomechanical performance of athletes at different levels. However, systematic studies on the psychological characteristics and biomechanical indicators of rock climbers at different levels remain limited. Objective: This study aimed to compare the psychological indicators (e.g., self-efficacy and sport motivation) and biomechanical characteristics (e.g., muscle activation levels, relative peak torque, and flexor-extensor peak torque ratios) of rock climbers to explore the differences and intrinsic relationships between athletes of different skill levels. The findings aimed to provide a theoretical basis for optimizing performance and designing training strategies. Methods: Twenty-two rock climbers participated in the study, including 11 elite athletes and 11 novice athletes. Psychological indicators were assessed using standardized questionnaires, including self-efficacy and five dimensions of sport motivation: Fun motivation, ability motivation, appearance motivation, health motivation, and social motivation. Biomechanical data were collected using the Noraxon DTS surface electromyography (sEMG) system and the Biodex System 4 isokinetic dynamometer, which measured muscle activation levels and the relative peak torque and flexor-extensor peak torque ratios of the shoulder, elbow, hip, knee, and ankle joints at speeds of 60°/s, 120°/s, and 180°/s. Muscle activation signals were normalized as %MVC, and peak torque values were extracted for analysis. The data were grouped by athlete level, and independent sample t-tests were conducted to compare group differences, with significance set at p < 0.05. Results: Elite athletes demonstrated significantly higher psychological indicators than novice athletes, particularly in self-efficacy (3.19 ± 0.671 vs. 2.77 ± 0.341) and fun motivation (3.28 ± 1.049 vs. 2.78 ± 0.47). Additionally, elite athletes exhibited higher muscle activation levels and relative peak torque in upper limb and core muscle groups compared to novice athletes (p < 0.05), indicating superior strength control and coordination. Conversely, novice athletes had relatively higher peak torque in lower limb muscle groups but showed deficiencies in strength balance and coordination. Conclusion: Significant differences were found in the psychological states and biomechanical characteristics of rock climbers at different levels. These differences likely contribute to variations in athletic performance. Elite athletes displayed stronger psychological advantages and superior strength in upper limb and core muscle groups. In contrast, novice athletes needed to enhance sport motivation and improve upper limb and core strength to develop comprehensive athletic abilities. This study provides a scientific basis for optimizing training strategies for rock climbers at different levels and lays a foundation for future research on the mechanisms underlying climbing performance.

Microplastics (MPs) are fragments with a diameter of less than 5 mm that have been directly manufactured or formed by the degradation of plastic waste. MPs are not only prone to bioaccumulation in the environment, but they also lead to the spread of micropollutants in the environment, thereby threatening human health ecological environment. The useful detection method of MPs and understanding their abundance, characteristics and toxicity are great essential for MPs removal and control. This work presented the current methods of MPs' detection, compared the abundance and characteristics of MPs in water, and reviewed MPs' toxicity to organisms. Furthermore, detailed policies intervention for plastics and MPs' mitigation have been focused which delineate for application of science and policy together with scientific evidence. Lastly, this study suggests more attention should be paid to the content of MPs in freshwater and organisms closely related to human life, as well as the toxicological toxicity of MPs in mammals.

ABSTRACT Soil water repellency, a crucial soil physical property, is widespread globally, affecting hydrology positively or negatively by impeding soil wetting. Nonetheless, research on soil and biocrust water repellency in degraded subtropical karst environments is lacking. This research examined how moss crusts affect soil water repellency in these environments using the Water Drop Penetration Time (WDPT) method. The research utilised moss crusts from degraded karst areas with varying levels of degradation, contrasting them with bare soils as controls. Results indicate that degraded subtropical karst soils (calcareous and yellow soils) exhibited no water repellency (WDPT < 5 s). Moss crusts notably enhanced water repellency consistently across various degradation stages, exhibiting slight water repellency (5 s ≤ WDPT < 60 s). Soil water repellency diminished following the removal of moss; however, it remained significantly elevated compared to bare soil. Factors such as soil water content, fine particle content, aggregate stability, organic carbon, total nitrogen, and total potassium were found to significantly influence water repellency. In bare soils, water repellency peaked at 10% water content, weakening thereafter, whereas moss crusts exhibited strongest repellency at 0% water content, diminishing as water content increased. Moreover, both moss crusts and bare soils showed heightened repellency with smaller particle sizes (< 0.05 mm). The hydrological impacts of biocrust‐induced water repellency vary, presenting both positive and negative effects that necessitate further investigation. This research establishes a foundation for upcoming studies on the impact of biocrusts on hydrology within these environments, providing essential theoretical knowledge for addressing soil erosion and loss in the context of global changes.