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The inherent complexity of cellulose, hemicellulose, and lignin contributes to the recalcitrance of lignocellulosic biomass, resulting in a low conversion efficiency and high cost of bioethanol conversion. Pretreatment methods that disrupt the plant cell structure of lignocellulose, such as straw, can significantly enhance the conversion efficiency. In this study, we utilized an acid-assisted mechanocatalytic depolymerization technique to pretreat rice straw, and the results demonstrated a significant disruption of the cellulose structure of the straw. Compared to the untreated straw, the particle size of pretreated straw reduced from 279 μm to 11.8 μm, the crystallinity of cellulose decreased from 43.05% to 22.71%, the specific surface area increased by 177%, and the surface oxygen-to-carbon ratio (O/C) ratio was enhanced by 75%. The changes in microstructure enabled the pretreated straw to achieve a total sugar yield of over 95% within 12 h of enzymatic hydrolysis, significantly superior to the 36.24% yield from untreated straw, the 45.20% yield from acid impregnated straw, and the 73.25% yield from ball milled straw. Consequently, acid-assisted mechanocatalytic depolymerization emerges as a highly effective pretreatment strategy to enhance both the enzymatic hydrolysis and the overall conversion efficiency of rice straw. [ABSTRACT FROM AUTHOR]

This study aimed to assess the association between preoperative neutrophil–lymphocyte ratio (NLR) and febrile urinary tract infection (fUTI) in patients who underwent percutaneous nephrolithotomy (PCNL). Patients and Methods: The clinical data of patients who underwent PCNL at our hospital between March 2020 and May 2023 were retrospectively analyzed. According to whether fUTI occurs after operation, collected data were divided to the patients into fUTI and non-fUTI. Univariate analysis, relative operating characteristic (ROC) curves and multivariate logistic regression analysis were performed on the data. Results: A total of 405 patients were enrolled in the study. The procedure was successfully performed in all patients, and the incidence of fUTI was 8.4% (34/405). Eight patients eventually developed sepsis, and the incidence of sepsis in fUTI patients was 23.5%. The result shows a significant correlation between NLR and fUTI (95% confidence interval [CI],1.21– 1.83, Odds ratio [OR]=1.49, p< 0.001). The predictive ability of NLR on the occurrence of fUTI was assessed by plotting relative operating characteristic (ROC) curves. The area under the curve (AUC) in the ROC curve for NLR was 0.718 according to the Youden index, and the best cut-off value of NLR was 2.71. Furthermore, logistic multiple regression model adjustment was carried out to further confirm the robustness of the relationship between NLR and fUTI. The results indicated robustness regardless of whether NLR was a continuous variable or a categorical variable. Conclusion: NLR can be used as a simple and effective preoperative indicator for the prediction of fUTI in patients undergoing PCNL. [ABSTRACT FROM AUTHOR]

Addressing the issues of low harvesting efficiency and high losses in current pod pepper harvesters, this study presents the design of a bionic comb finger pod pepper picking device and an inclined double-spiral bell pepper harvester to improve the harvest rate and reduce loss rate. Through the utilization of discrete element simulation software EDEM, a discrete element model for pod peppers is established. Additionally, a simulation platform for ground drop loss during pod pepper picking is developed, enabling exploration of the movement trajectory and velocity changes of the pod pepper elements. The study also conducts an analysis on the impact of the speed of the picking rollers X1, the feeding speed of pod peppers X2, and the spacing between the two picking rollers X3 on ground drop losses. Based on the results of the single-factor test, the Box–Behnken response surface test was used to optimize the working parameters of the picking device, which resulted in the optimal combination of the working parameters of the picking device: the speed of the picking rollers was 680.41 rpm, the feeding speed of the pod peppers was 0.5 m/s, and the spacing between the two picking rollers was 12 mm, which resulted in the loss rate of pod peppers on the floor of the ground being 3.526%. [ABSTRACT FROM AUTHOR]

Earth-air heat exchanger (EAHE) is a low-carbon device that use renewable energy to improve the thermal environment of buildings by heating/cooling the air with the help of the thermal inertia of the soil. However, the traditional earth-air heat exchanger has the problem of large fluctuations in air temperature with the outdoor air temperature fluctuations. A system that combines an air supply chamber with an EAHE is proposed to address this problem. The outdoor air first enters the underground air supply static pressure chamber for initial cooling, and then enters the EAHE treatment. To investigate the effect of this air supply static pressure chamber on the cooling performance of EAHE, a three-dimensional numerical model was developed in ANSYS Fluent and validated with field measurement data. Then comparative studies of the EAHE system with a supply air static pressure chamber and the traditionnal EAHE system were conducted under summer conditions in Chongqing (China). The results show that the air supply static pressure chamber can reduce the EAHE outlet air temperature fluctuation by 31.98% at the maximum under the continuous operation of different air volume systems for 7 days. At the same time, the cooling capacity can be increased by 19.89% at maximum compared with the conventional EAHE cooling capacity.

Objectives: To develop a real-time abdominal T2 mapping method without requiring breath-holding or respiratory-gating. Methods: The single-shot multiple overlapping-echo detachment (MOLED) pulse sequence was employed to achieve free-breathing T2 mapping of the abdomen. Deep learning was used to untangle the non-linear relationship between the MOLED signal and T2 mapping. A synthetic data generation flow based on Bloch simulation, modality synthesis, and randomization was proposed to overcome the inadequacy of real-world training set. Results: The results from simulation and in vivo experiments demonstrated that our method could deliver high-quality T2 mapping. The average NMSE and R2 values of linear regression in the digital phantom experiments were 0.0178 and 0.9751. Pearson's correlation coefficient between our predicted T2 and reference T2 in the phantom experiments was 0.9996. In the measurements for the patients, real-time capture of the T2 value changes of various abdominal organs before and after contrast agent injection was realized. A total of 33 focal liver lesions were detected in the group, and the mean and standard deviation of T2 values were 141.1 ± 50.0 ms for benign and 63.3 ± 16.0 ms for malignant lesions. The coefficients of variance in a test–retest experiment were 2.9%, 1.2%, 0.9%, 3.1%, and 1.8% for the liver, kidney, gallbladder, spleen, and skeletal muscle, respectively. Conclusions: Free-breathing abdominal T2 mapping is achieved in about 100 ms on a clinical MRI scanner. The work paved the way for the development of real-time dynamic T2 mapping in the abdomen. Key Points: • MOLED achieves free-breathing abdominal T2 mapping in about 100 ms, enabling real-time capture of T2 value changes due to CA injection in abdominal organs. • Synthetic data generation flow mitigates the issue of lack of sizable abdominal training datasets. [ABSTRACT FROM AUTHOR]