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Three-Dimensional (3D) Synthetic Aperture Radar (SAR) holds great potential for applications in fields such as mapping and disaster management, making it an important research focus in SAR technology. To advance the application and development of 3D SAR, especially by reducing the number of observations or antenna array elements, the Aerospace Information Research Institute, Chinese Academy of Sciences, (AIRCAS) has pioneered the development of the full-polarimetric Microwave Vision 3D SAR (MV3DSAR) experimental system. This system is designed to serve as an experimental platform and a source of data for microwave vision SAR 3D imaging studies. This study introduces the MV3DSAR experimental system along with its full-polarimetric SAR data set. It also proposes a set of full-polarimetric data processing scheme that covers essential steps such as polarization correction, polarization coherent enhancement, microwave vision 3D imaging, and 3D fusion visualization. The results from the 3D imaging data set confirm the full-polarimetric capabilities of the MV3DSAR experimental system and validate the effectiveness of the proposed processing method. The full-polarimetric unmanned aerial vehicle -borne array interferometric SAR data set, released through this study, offers enhanced data resources for advancing 3D SAR imaging research.

Abstract Oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) are key bioenergetics pathways. The machineries for both processes are localized in mitochondria. Secondary OXPHOS defects have been documented in patients with primary FAO deficiencies, and vice versa. However, the underlying mechanisms remain unclear. Intrigued by the observations that regulation of supercomplexes (SCs) assembly in a mouse OXPHOS deficient cell line and its derivatives is associated with the changes in lipid metabolism, a proteomics analysis is carried out and identified mitochondrial trifunctional protein (MTP) subunit alpha (hydroxyacyl‐CoA dehydrogenase trifunctional multienzyme complex subunit alpha, HADHA) as a potential regulatory factor for SCs assembly. HADHA‐Knockdown cells and mouse embryonic fibroblasts (MEFs) derived from HADHA‐Knockout mice displayed both reduced SCs assembly and defective OXPHOS. Stimulation of OXPHOS induced in cell culture by replacing glucose with galactose and of lipid metabolism in mice with a high‐fat diet (HFD) both exhibited increased HADHA expression. HADHA Heterozygous mice fed with HFD showed enhanced steatosis associated with a reduction of SCs assembly and OXPHOS function. The results indicate that HADHA participates in SCs assembly and couples FAO and OXPHOS.

ABSTRACT Fatigue vibration is a primary cause of fruit damage during transportation. Drawing on the Palmgren–Miner fatigue accumulation damage theory and the correlation between fruit vibration damage characteristics and external vibration excitation, this paper proposes a fruit vibration fatigue accumulation damage model and its method for parameter determination. Using pears as the research objects, we conducted fatigue damage vibration and critical fatigue damage vibration tests under various conditions to determine the vibration fatigue constant of the pears. By utilizing the critical value of the damage area specified in the pear grading standard for premium grade, we derived the threshold acceleration value for pear damage. These findings serve as a technical foundation for advancing our understanding of fruit vibration fatigue damage mechanisms and guiding the development of cushioning packaging to protect fruit from vibrations.

ABSTRACTEfforts have been made to streamline the abstract as follows. If further changes are made we are concerned that the integrity of the content may be compromised. We hope you will understand. This study aimed to investigate the impact damage experienced by Pucheng crisp pears during various stages, including harvest, transportation, and processing. Drop impact tests were conducted on pears, considering drop height and collision contact material as factors influencing damage. The bruise area was used as an indicator for damage evaluation. Additionally, the pressure-sensitive film technique was employed to measure the contact stress distribution characteristics of Pucheng crisp pears after the drop impact. The relationship between contact stress distribution and damage area was examined, and the stress area range close to the damage area was determined. The results revealed that the damage area of pears increased linearly with the increasing drop height. Among the four contact materials, foam board exhibited the best cushioning properties, with a maximum safe drop height of 20 cm. The pressure distribution tended to follow a normal distribution, with a pressure range of 0.2-0.3 MPa covering the largest area, corresponding to the majority of the bruise area on the pears. Furthermore, the pressure area and average pressure were found to be related to the severity of bruising. When pears were dropped onto steel, rubber plate and corrugated board, for the former two the stress area exceeding 0.2 MPa closely approximated the damage area, with an average relative error of 7.2%. For the latter, the closest range was above 0.3 MPa, with an average relative error of 3.6%. However, when dropped onto foam board, the average relative error was 75%. This research provides valuable insights for designing packaging tools to minimize damage and serves as a theoretical basis for predicting and assessing pear bruise area using finite element analysis.

It is important to have an understanding of the mechanical properties of crisp pears in order to assess their resistance to damage and investigate their compression patterns. Through tensile and compression tests, this study measured the elastic modulus, tensile strength, compressive strength and other parameters of Pucheng Crisp Pear, explored the effect of storage temperature on the mechanical properties of crisp pears, and developed a storage temperature-mechanical property prediction model. The results of the pear peel tensile test showed that both the tensile strength of the peel decreased with the increase of storage temperature, while the modulus of elasticity was decreased. There were no significant differences in the tensile strength and modulus of elasticity of the peel at the same storage temperature. The results of the flesh compression test also showed a decrease in compressive strength and modulus of elasticity with increasing storage temperature. Under the same storage condition, the compressive strength and modulus of elasticity of the pear flesh differed significantly in different directions. The correlation coefficients for tensile strength and modulus of elasticity in both the axial and radial directions for the peel and flesh of crisp pears were high, and provided accurate predictions for mechanical characteristics. These findings could be used to inform the development of mechanical equipment, post-harvest storage methods, and the reduction of mechanical damage in all working stages of crisp pears.

The mechanical properties of kiwifruit serve as the foundation for mechanical damage. In this work, the effect of hardness on the mechanical properties of kiwifruit was explored, and a hardness-mechanical property prediction model was developed. The results in this study showed that the tensile strength of the kiwifruit peel increased with decreasing hardness by 0.51, 0.75, 0.83, and 1.02 MPa in the axial direction and 0.48, 0.68, 0.92, and 1.08 MPa in the radial direction, respectively. While the peel’s elastic modulus decreased by 21.15, 14.03, 11.87, and 10.52 MPa in the axial direction and 15.04, 10.68, 8.45, and 7.54 MPa in the radial direction. At the same ripening stage, peel tensile strength did not differ significantly (P > .05), whereas peel modulus of elasticity was greater in the axial direction than in the radial direction. The results of the flesh compression test showed that the compressive strength of the flesh decreased with decreasing hardness to 0.36, 0.25, 0.09, and 0.06 MPa in the axial direction and 0.36, 0.23, 0.11, and 0.06 MPa in the radial direction, respectively. The modulus of elasticity also decreased to 1.05, 0.82, 0.42, and 0.32 MPa in the axial direction and 0.26, 0.45, 0.80, and 1.15 MPa in the radial direction, respectively. The compressive strength and modulus of elasticity of kiwifruit flesh did not differ significantly in the axial and radial directions at the same stage of ripening (P > .05). The model’s accuracy is demonstrated by correlation coefficients of tensile strength (compressive strength) and elastic modulus of kiwifruit peel and pulp in axial and radial directions, which were 0.97, 0.99 (0.99, 0.99), and 0.93, 0.90 (0.96, 0.99), respectively, for anticipating the mechanical characteristics of peel and flesh. It can provide theoretical and data references for post-harvest kiwifruit to reduce the mechanical damage.

Objective: For computer-aided Chinese medical diagnosis and aiming at the problem of insufficient segmentation, a novel multi-level method based on the multi-scale fusion residual neural network (MF2ResU-Net) model is proposed. Methods: To obtain refined features of retinal blood vessels, three cascade connected U-Net networks are employed. To deal with the problem of difference between the parts of encoder and decoder, in MF2ResU-Net, shortcut connections are used to combine the encoder and decoder layers in the blocks. To refine the feature of segmentation, atrous spatial pyramid pooling (ASPP) is embedded to achieve multi-scale features for the final segmentation networks. Results: The MF2ResU-Net was superior to the existing methods on the criteria of sensitivity (Sen), specificity (Spe), accuracy (ACC), and area under curve (AUC), the values of which are 0.8013 and 0.8102, 0.9842 and 0.9809, 0.9700 and 0.9776, and 0.9797 and 0.9837, respectively for DRIVE and CHASE DB1. The results of experiments demonstrated the effectiveness and robustness of the model in the segmentation of complex curvature and small blood vessels. Conclusion: Based on residual connections and multi-feature fusion, the proposed method can obtain accurate segmentation of retinal blood vessels by refining the segmentation features, which can provide another diagnosis method for computer-aided Chinese medical diagnosis.

High resolution remains a primary goal in the advancement of synthetic aperture radar (SAR) technology. The backprojection (BP) algorithm, which does not introduce any approximation throughout the imaging process, is broadly applicable and effectively meets the demands for high-resolution imaging. Nonetheless, the BP algorithm necessitates substantial interpolation during point-by-point processing, and the precision and effectiveness of current interpolation methods limit the imaging performance of the BP algorithm. This paper proposes a TSU-ICSI (Time-shift Upsampling-Improved Cubic Spline Interpolation) interpolation method that integrates time-shift upsampling with improved cubic spline interpolation. This method is applied to the BP algorithm and presents an efficient implementation method in conjunction with the GPU architecture. TSU-ICSI not only maintains the accuracy of BP imaging processing but also significantly boosts performance. The effectiveness of the BP algorithm based on TSU-ICSI is confirmed through simulation experiments and by processing measured data collected from both airborne SAR and spaceborne SAR.

Neoadjuvant chemotherapy (NAC) is increasingly widely used in breast cancer treatment, and accurate evaluation of its response provides essential information for treatment and prognosis. Thus, the imaging tools used to quantify the disease response are critical in evaluating and managing patients treated with NAC. We discussed the recent progress, advantages, and disadvantages of common imaging methods in assessing the efficacy of NAC for breast cancer.

ABSTRACT Radio frequency (RF) drying is a rapid dehydration technique that reduces water activity and extends the shelf life of agricultural products. In this study, the drying characteristics of jujube during HARF and hot air (HA) were investigated, and quality analyses, such as color, vitamin C (VC) and total flavonoid content (TFC), of jujube were performed. The drying curves revealed that the drying time used to reduce the moisture content from 81.7 to 6.0% on a dry basis was 360 and 1320 min using HARF drying and hot air (HA) drying, respectively. The logarithmic model was the best to describe the HARF drying process with R 2, RMSE and SSE values of 0.998, 0.00508 and 0.000306, respectively. Quality analysis demonstrated significant differences in color, VC content and total flavonoid content between the HARF and HA treatments during the drying process and storage periods (P > 0.5), and the HARF-dried jujube product performed much better than that dried by HA. Compared with HA drying, HARF drying showed a shorter drying time, higher drying efficiency and better product quality, indicating that HARF drying was a more promising drying method for jujube with acceptable product quality.

This dataset presents the mitochondrial genome variants associated with oncocytic tumors. These data were obtained by Sanger sequencing of the whole mitochondrial genomes of oncocytic tumors and the adjacent normal tissues from 32 patients. The mtDNA variants are identified after compared with the revised Cambridge sequence, excluding those defining haplogroups of our patients. The pathogenic prediction for the novel missense variants found in this study was performed with the Mitimpact 2 program.

Epstein–Barr virus (EBV) is a major contributor to nasopharyngeal carcinoma (NPC) tumorigenesis. Mitochondria have been shown to be a target for tumor viral invasion, and to mediate viral tumorigenesis. In this study, we detected that mitochondrial morphological changes in tumor tissues of NPC patients infected with EBV were accompanied by an elevated expression of BHRF1, an EBV encoded protein homologue to Bcl-2. High expression of BHRF1 in human NPC cell lines enhanced tumorigenesis and metastasis features. With BHRF1 localized to mitochondria, its expression induced cyclophlin D dependent mitochondrial membrane permeabilization transition (MMPT). The MMPT further modulated mitochondrial function, increased ROS production and activated mitophagy, leading to enhanced tumorigenesis. Altogether, our results indicated that EBV-encoded BHRF1 plays an important role in NPC tumorigenesis through regulating cyclophlin D dependent MMPT.

A flexible chassis (FC) is a type of electric vehicle driven by in-wheel motors that can be used in narrow conditions in agricultural facilities. The FC is composed primarily of four off-center steering mechanisms (OSMs) that can be controlled independently. Various FC operation modes can be achieved including cross motion (CM), in-place rotation (IR), diagonal motion (DM), and steering motion (SM). However, it is difficult to achieve satisfactory motion mode switching (MMS) results under traditional distribution control methodologies due to a lack of linkage relationships between the four OSMs. The goal of this study was to provide a coupling control method that can cope with this problem. First, dynamic MMS models were derived. Then, an MMS coupling error (CE) model was derived based on coupling control and Lyapunov stability theory. Second, a fuzzy proportional integral derivative (PID) controller with self-tuning parameters was designed to reduce the CE during MMS. A fuzzy PI controller was also employed to improve response times and decrease OSM tracking motion steady-state error. Finally, MATLAB/Simulink simulations were performed and experimentally validated on hard pavement. The results showed that the proposed methodology could effectively reduce CE and guarantee MMS control stability while substantially shortening response times. The proposed methodology is effective and feasible for FC MMS.

Cherry samples were treated with cold plasma under different voltages (40, 60, 80 kV) and different treatment durations (60, 80, 100, 140 s), then stored in a refrigerator at 0 °C. Data on the decay rate, respiration rate, and physiological properties of the cherries and their correlational relationships after different treatments of cold plasma were collected under the conditions of ambient temperature and dry air. The decay rate, respiration rate, total soluble solids, total phenol, flavonoids, anthocyanin, VC, titratable acidity, firmness, and a* value were investigated at regular intervals to analyze the quality of the cherries under different treatment conditions. Additionally, the total colony number was estimated at the end of storage. The results indicated that cold plasma treatment under moderate conditions was effective for prolonging cherry storage, inactivating microorganisms, decreasing the decay rate, and inhibiting respiration with either no compromise on the cherry quality or only a slightly noticeable influence. A significant positive correlation was found between the decay rate and respiration rate, as well as between the VC content and titratable acidity. Antioxidant contents and firmness were found to be negatively correlated with the a* value. In conclusion, this study demonstrated that cold plasma has potential applications in the storage and preservation of cherries. [ABSTRACT FROM AUTHOR]

In this paper, we study a four-wheel, individual steering and four-wheel, individually driven, electric chassis, named the flexible chassis. A 2-FOF nonlinear steering model for the flexible chassis is established based on the "magic formula" tire model and the Ackermann steering theorem at low speed. Also, a new control method based on the fuzzy strategy is proposed for its sideslip angle control. The left front-wheel steering angle is inputted into the simulation of the vehicle, and the left-rear wheel angle is controlled by the fuzzy controller to make the sideslip angle zero. Also, the remaining steering angle of the other two wheels, which meet the Ackermann theorem, are adjusted. Comparisons between simulations of the front-wheel steering, four-wheel, proportional steering and the newly proposed steering indicate that the new control algorithm in this paper is effective. [ABSTRACT FROM AUTHOR]