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White clover (Trifolium repens L.) is a herbaceous, perennial plant that has become one of the most widely distributed legumes in the world. It is cultivated in a large area in China, mainly for animal husbandry feed, artificial grassland, garden greening and ecological construction. In 2022, leaf spot disease was observed on white clover in China's Sichuan province, and the strain was isolated. The pathogenicity of the isolates was confirmed using Koch's postulates. The fungus was/were red on PDA, and two types of conidia were observed after 6 days of cultivation on straw juice medium. The pathogen was identified as Fusarium graminearum by the amplification of part of the ITS and TEF-α genes and by phylogenetic analysis. Currently, this is the first report to indicate that the causal agent of leaf spot disease on white clover is F. graminearum. • The first report of Fusarium graminearum Causing Leaf Spot of white clover (Trifolium repens) in China. • Fusarium graminearum was identified by ITS and TEF1-α genes. • This can be helpful for the control of white clover leaf spot. [ABSTRACT FROM AUTHOR]

The main obstacles in lithium-ion battery are limited by rate performance and the rapid capacity fading of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811). Herein, a novel three-dimensional (3D) hierarchical coating material has been fabricated by in situ growing carbon nanotubes (CNTs) on the surfaces of Ni–Al double oxide (Ni–Al-LDO) sheets (named as LDO&CNT) with Ni–Al double hydroxide (Ni–Al-LDH) as both the substrate and catalyst precursor. The resultant LDO&CNT nanocomposites are uniformly coated on the surfaces of NCM811 by the physical mixing method. The rate capability of the resultant cathode material retains to 78.80% at a current rate of 3C. Its capacity retention increases by 6.7–14.42% compared with pristine NCM811 after 100 cycles within a potential range of 2.75–4.3 V at 0.5C. The improved rate capability and cycle performance of NCM811 are assigned to the synergistic effects between Ni–Al-LDO and CNTs. The hierarchical LDO&CNT nanocomposites coating on the surface of NCM811 avoids the aggregation of conductive CNTs and the stacking of Ni–Al-LDO nanosheets. Furthermore, it accelerates Li+ and electrons shuttle and reduces the reaction of Li 2 O with H 2 O and CO 2 in air, which results in Li 2 CO 3 and LiOH alkali formation on the NCM811 surface. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effect of different drying temperatures and airflow speeds on the number and species of volatile components in infrared-assisted spouted bed dried (IRSBD) Shiitake mushrooms. The dynamics changes in volatile components (determined by HS-SPME-GC-MS) during drying under optimal conditions were also monitored. Results revealed that the maximum number of volatile components (69 species) was observed at a temperature of 55 °C and airflow speed of 8.0 m/s, of which the volatile components in Shiitake mushrooms varied significantly over the drying process at this condition. Fresh Shiitake mushrooms mainly composed of volatile substances such as alcohols, ketones and acids. During the early drying stage (0–40 min), the levels of alcohols and ketones gradually decreased, while the species and levels of aldehydes, esters, and volatile sulfur-containing compounds (VSCs) increased. In the middle stage (40–120 min), levels of alcohols, esters, aldehydes, acids, and alkanes species increased, while the levels of VSCs decreased. For the last stage (120–200 min), the levels of sulfur-containing heterocyclic compounds, aldehydes, esters, acids, pyrazines, and alkanes were all increased. The findings of this study provide insights into the flavor formation mechanism during IRSBD of Shiitake mushrooms and offer a theoretical reference for the production of industrial flavorful dried goods. • HS-SPME-GC-MS was used to monitor volatile compounds of IRSBD Shiitake mushrooms. • Volatile compounds of samples were dynamic changed during whole stage of IRSBD. • 55 °C and 8.0 m/s airflow speed was suitable for yielding rich flavor product. [ABSTRACT FROM AUTHOR]

Sodium bicarbonate medium ultrasound pre-treatment can enhance the freeze-drying process of blueberries, but the quality of dried products cannot meet the actual production needs. To yield higher quality products, chitosan coating was applied in blueberry sodium bicarbonate medium ultrasound pre-treatment enhanced freeze-drying process. The improvement effect of different chitosan coating methodologies on the procedure of blueberry freeze-drying, enhanced by ultrasound pre-treatment in sodium bicarbonate medium, was investigated. These include: chitosan solution soaking alone (CH-A), chitosan medium ultrasound treatment (US-CH), first sodium bicarbonate medium ultrasound treatment then chitosan solution soaking (US-NaHCO 3 + CH) and first sodium bicarbonate soaking followed by chitosan medium ultrasound treatment (NaHCO 3 + US-CH). While the treatments that presoaking in sodium bicarbonate solution (NaHCO 3 -A), water medium ultrasound treatment (US-W) and sodium bicarbonate medium ultrasound treatment (US-NaHCO 3) were used as the control groups. Results demonstrated that ultrasound treatment and sodium bicarbonate soaking have positive effect on improving the freeze-drying characteristics of blueberries, while chitosan coating has a negative effect. Chitosan coating has a significant effect on strengthening limit effect of blueberry skin on juice overflow and weakening moisture absorption capacity of dried blueberry. US-NaHCO 3 + CH pretreatment yielded the best results for blueberry freeze-drying. • Dried blueberry quality is significantly improved after chitosan (CH) coating. • Drying efficiency is still maintained in a high level even after coating blueberry with chitosan. • Ultrasound-NaHCO 3 + CH is found to be the best strategy for blueberry freeze-drying. [ABSTRACT FROM AUTHOR]

Recently, more and more studies have begun to use deep learning to decode and classify EEG signals. The use of deep learning has led to an increase in the classification accuracy of motor imagery (MI), but the problem of taking a long time to calibrate in brain–computer interface (BCI) applications has not been solved. To address this problem, we propose a novel Riemannian geometry and deep domain adaptation network (RGDDANet) for MI classification. Specifically, two one-dimensional convolutions are designed to extract temporal and spatial features from the EEG signals, and then the spatial covariance matrices are utilized to map the extracted features to Riemannian manifolds for processing. In order to align the source and target features' distributions on the Riemannian manifold, we propose a Symmetric Positive Definite (SPD) matrix mean discrepancy loss (SMMDL) to minimize the distance between two domains. To analyze the feasibility of the method, we conducted extensive experiments on BCIC IV 2a and BCIC IV 2b datasets, respectively, and the results showed that the proposed method achieved better performance than some state-of-the-art methods. • A novel network structure based on the combination of CNN and Riemannian geometry. • Domain adaptation is used to improve the performance of cross-session classification. • A novel domain loss function based on Riemannian geometry. • Excellent performance with fewer unlabeled samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Our research examines the critical considerations of driving factors that contribute to eco-efficiency in grain production as a pivotal component of China's energy transition. As China strives to align agricultural practices with sustainable energy objectives, it becomes imperative to identify and understand the key determinants that impact eco-efficiency in grain production. This research unveils the intricate dynamics at play within the intersection of grain production and China's energy transition. It employs super-SBM-windows-DEA model, which accounts for unexpected outputs, to assess the eco-efficiency of grain production across China's 31 provinces spanning the years from 1998 to 2021. Furthermore, it delves into the spatiotemporal evolution characteristics, employing the panel Tobit model to dissect the mechanisms governing various influencing factors. Currently, China's grain production eco-efficiency registers at a relatively low level. The study identifies a pattern where major grain-consuming areas exhibit the highest efficiency, followed by major grain-producing areas, and the lowest efficiency is observed in regions where grain production and consumption are in balance. Over the decade from 1998 to 2021, China's grain production eco-efficiency follows a fluctuating pattern of increase, decrease, and increase, indicative of a generally stable overall trend. The spatial distribution of grain production eco-efficiency showcases a pattern of higher concentrations in peripheral areas and lower concentrations in central areas, and the spatial correlation reveals a randomly dispersed distribution. Several factors wield significant influence: economic development level, agricultural production structure, urban-rural income gap, and labor-to-planting area ratio all exert significant positive effects on grain production eco-efficiency. Conversely, disaster level and replanting index are found to significantly inhibit grain production eco-efficiency. These findings are valuable for policymakers, agricultural stakeholders, and environmental advocates seeking to steer China toward a more sustainable and energy-efficient grain production landscape. • It becomes imperative to identify the key determinants that impact eco-efficiency in grain production. • This research sheds light on the intricate interplay between grain production and energy transition in China. • The results indicate the overall level of ecological efficiency in China's grain production is relatively low. • While economic development, urban-rural income gap exert significant inhibitory effects. [ABSTRACT FROM AUTHOR]

Hidden distresses of asphalt pavement are hidden dangers in the service of expressways. Efficient and accurate detection of hidden distresses is of great importance for maintaining and managing the expressways suffering from them. In this study, the intelligent detection technology of asphalt pavement hidden distresses was studied using the object detection algorithm and ground penetrating radar (GPR) image data. A GPR image data set was established to train and test the object detection model. And the distresses samples in the data set include settlement, hidden cracks and loosening. According to the distribution of hidden distresses in GPR image data, a two-way object detection model for targets of different scales was proposed, and each part of the two-way model was optimized and improved based on the basic model. At the same time, a copy-and-paste data enhancement scheme was designed to expand and balance the number of distress data samples. The final model greatly improved the detection accuracy of asphalt pavement hidden distresses. The results of the model test showed that the two-way object detection model proposed in this paper can effectively improve the detection accuracy of small-sized distress objects. Compared to the basic model, the final model had an increase of 17.9% in the average precision (AP) of small objects and a 9.9% increase in the comprehensive index AP (0.5: 0.95). The results of the ablation experiment show that the optimization methods for each part of the model improved the comprehensive detection effect of the model. When compared with other object detection models, the final model was superior to other models in all AP indicators, and had obvious advantages in the detection accuracy of the three types of hidden distresses. The confusion matrix of the test results of the final model showed that the recall rate of the final model for the three types of hidden distresses was above 96%. Thus, applying the final model established in this study to actual road detection can effectively improve the efficiency of distress detection in GPR images. • Established GPR image datasets of asphalt pavement hidden distresses. • Proposed methods to improve the problem of the insufficient and unbalanced number of distress samples in the GPR data. • Designed a object detection model to effectively improve the detection accuracy of small-sized distress objects. • Detailed analysis was conducted on the design process and effectiveness verification of the proposed model. [ABSTRACT FROM AUTHOR]

• A moving boundary model for flow in a multilayered low-permeability reservoir is built. • The number of layers can be arbitrary in the model. • The exact similarity solution of the nonlinear model is obtained. • The exact analytical solution can reduce to the solution for Darcy flow. • A formula for the relative error of the transient pressure caused by ignoring the moving boundary is presented. A nonlinear generalized multiple moving boundary model of one-dimensional non-Darcy flow in heterogeneous multilayered low-permeability porous media with a threshold pressure gradient is constructed, in which the total rate of fluid injection into the porous media remains constant. The number of layers in the model can be arbitrary, and thus the generalized model will be very suitable for describing the one-dimensional non-Darcy flow characteristics in low-permeability reservoirs with strong heterogeneity. Through the similarity transformation method, the exact analytical solution of the multiple moving boundary model is obtained, and the formula for the subrate of fluid injection into every layer is provided. Moreover, it is strictly proved that the exact analytical solution can reduce to the solution of Darcy flow as the threshold pressure gradient in different layers simultaneously tends to zero. Through the exact analytical solution, the effects of the layer threshold pressure gradient, the layer permeability ratio, and the layer elastic storage ratio on the moving boundaries, the spatial pressure distributions, the transient pressure, and the layer subrate in low-permeability porous media are discussed. Through comparison of the exact analytical solutions, it is also demonstrated that incorporation of the multiple moving boundary conditions is very necessary in the modeling of non-Darcy flow in heterogeneous multilayered porous media with a threshold pressure gradient, especially when the threshold pressure gradient is large. In particular, an explicit formula is presented for estimating the relative error of the transient pressure introduced by ignoring the moving boundaries in the modeling. All in all, solid theoretical foundations are provided for non-Darcy flow problems in stratified reservoirs with a threshold pressure gradient. They can be very useful for strictly verifying numerical simulation results, and for giving some guidance for project design and optimization of layer production or injection during the development of heterogeneous low-permeability reservoirs and heavy oil reservoirs so as to enhance oil recovery. [ABSTRACT FROM AUTHOR]

Starch retrogradation during freeze drying is a contributor to an undesirable decrease in the viscosity of soup prepared from instant soup with high starch content. Monitoring starch retrogradation during drying is therefore of importance if such a process is to be optimized. Here, cream mushroom soup was used as an example of high-starch instant soup. Drying and quality characteristics of the soup during freeze drying was first studied. Although freeze drying preserved much quality of the soup, it led to significant decrease in the viscosity. Following the data on starch retrogradation, drying characteristics and quality (in terms of whiteness, Shrinkage ratio and rehydration behavior) of the freeze-dried product, three-step hybrid drying strategy viz. microwave drying (0.8 W/g, for 1 h) + freeze drying (50 °C, for 4 h) + microwave drying (0.8 W/g, until the end of drying) was successfully developed to avoid viscosity reduction while maintaining other quality characteristics of the soup. • Drying of a complex food system viz. instant cream mushroom soup was studied. • Starch retrogradation behavior of the soup during freeze drying was analyzed. • Hybrid drying strategy is proposed to prevent viscosity drop of reconstituted soup. • Quality, in particular, viscosity of reconstituted soup was well maintained. • Required drying time could also be significantly shortened. [ABSTRACT FROM AUTHOR]

It is well known that the Non-Newtonian Bingham fluid flow in porous media does not obey the conventional linear Darcy's law due to the yield stress for the Bingham fluid: There exists a threshold pressure gradient, which means that the seepage flow only happens when the threshold pressure gradient is overcome. The principle of non-Darcy seepage flow with the threshold pressure gradient is also applicable into the situation of the fluid flow in the low-permeable porous media. Here, a nonlinear moving-boundary mathematical model is built for the semispherical centripetal non-Darcy seepage flow with the threshold pressure gradient in a three-dimensional infinite heavy oil reservoir with the type of Bingham fluid; wherein the moving boundary conditions are incorporated for describing the effect of the threshold pressure gradient. In consideration of the strong nonlinearity of the model, the similarity transformation method is applied into obtaining the exact analytical solution of the model. In order to keep full self-similarity for the model, the inner boundary condition is set as variable flow rate that increases linearly with the time. As a result, an exact analytical solution for the nonlinear moving-boundary mathematical model of semispherical centripetal non-Darcy seepage flow with the threshold pressure gradient is obtained. The existence and the uniqueness of the exact analytical solution are also strictly proved. It is also theoretically proved that as the threshold pressure gradient tends to zero, the exact analytical solution can be reduced to that of a mathematical model of semispherical centripetal Darcy's seepage flow. The presented exact analytical solution can be used for strictly verifying the validity of the numerical methods for solving the three-dimensional moving boundary models of non-Darcy seepage flow with the threshold pressure gradient in the actual engineering problems. From the exact analytical solution, it is also revealed that when the threshold pressure gradient exists, the spatial pressure distribution exhibits an instructive feature of compact support; as the threshold pressure gradient tends to zero, the sensitivity of its effect on the transient distance of the moving boundary and the transient pressure will grow, which reveals the difficulty in accurately determining the position of the moving boundary by the numerical methods and the serious uncertainty problem in the interpretation of the threshold pressure gradient by the pressure transient analysis method in engineering as the threshold pressure gradient is rather small. Through the comparison of the two different exact analytical solutions that corresponds to the two different models with and without incorporating the moving boundary conditions for describing the effect of the threshold pressure gradient, it is demonstrated that when the moving boundary conditions are not incorporated in the modeling, the effect of the threshold pressure gradient on the spatial pressure distribution, the transient pressure and the productivity index can be overestimated largely. Therefore, it is very necessary to incorporate the moving boundary conditions in the modeling of non-Darcy seepage flow with the threshold pressure gradient. The study in the paper definitely provides solid theoretical basis of fluid mechanics for the relevant engineering applications in the development of heavy oil reservoirs and low-permeable reservoirs in petroleum engineering and in the development of water resources in low-permeable formations in hydraulic engineering. • A moving boundary model of centripetal seepage flow of Bingham fluid is built. • Exact analytical solution of the model is obtained by similarity transformation. • It can be used for verifying the validity of three-dimensional flow simulation. • Existence and uniqueness of the exact analytical solution are proved strictly. • Moving boundary must be incorporated in modeling this Bingham fluid flow problem. [ABSTRACT FROM AUTHOR]