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This paper proposes a new motor structure based on the electromagnetic radial force drive. The radial electromagnetic force is converted into output torque through the meshing action of the gear pair, thereby significantly improving the torque density. In this study, the magnetic circuit characteristics and air gap flux density distribution are analyzed and verified through finite-element method. The analysis results of the radial force on the internal gear as a function of time are given. Then the gear pair model was designed, and its feasibility was verified. Evaluating the performance of the motor, it can reach a torque density of 13 Nm/L in a small volume of 0.16 L. The proposed motor structure has significant advantages in space-constrained low-speed and high-torque applications.

Deep learning (DL) models for change detection (CD) are affected by the changed/unchanged and hard/easy sample imbalance during the training process. Most of the loss functions for solving the sample imbalance problem are a static loss which is difficult to adapt to the variation of data distribution. In this article, we propose a dynamic method termed dynamic adaptive focal loss (DAFL) function. Specifically, we first statistically count the number of changed/unchanged samples in different batches of training data and a dynamic weighting factor is constructed to dynamically and adaptively balance their proportions. Furthermore, a dynamic modulation factor is proposed to suppress the hard/easy sample imbalance. In addition, we employ a CD model based on a progressive scale expansion network (PSENet), which is trained using DAFL for remote sensing images. Experimental results on three CD datasets (CDDs, Sun Yat-sen University (SYSU)-CD, and LEarning VIsion Remote Sensing (LEVIR)-CD) indicate that DAFL outperforms all baseline approaches. Our proposed method achieves the maximum improvement, with an $F1$ -score of 0.33%, 0.8%, and 0.94% for sufficient sample size, and 2.15%, 2.61%, and 3.89% for small-sample size, respectively. This advancement is crucial for the application of CD, which provides an alternative method for solving sample imbalance in the condition of varying sample sizes, especially small sample conditions that are common in the real scenario.

The spatiotemporal analysis of crop spectral features has become a mainstream method for identifying crop stresses. However, current spatiotemporal feature extraction methods fragment the relationship between time and space, resulting in low accuracy in identifying different stresses in crops. The spatiotemporal cube (ST-cube) model has the advantage of integrating spatiotemporal features by unifying time and space modeling. This study proposes an ST-cube model to mine spatiotemporal changes under different rice stresses and identify heavy metal stress in rice. First, the stress information in the enhanced vegetation index (EVI) time series of rice pixels was extracted. Second, the ST-cube was segmented to obtain continuous spatiotemporal units of the stressed rice. Finally, an intraannual global spatiotemporal stability index (GSTSintra) and an interannual global spatiotemporal stability index (GSTSinter) were constructed to evaluate the spatiotemporal stability of rice under stresses. A case study was performed on a rice planting area in Zhuzhou, Hunan, China, during 2019–2021 using Sentinel-2A images and field measurement data. The results indicated that rice under the stress exhibits significant spatial clustering. Regardless of the year, the spatial distribution and proportion of GSTSintra values were similar. In the three-year analysis, most GSTSinter values were close to 1, indicating that the sources of the stress experienced during the years were similar. GSTSintra and GSTSinter accurately revealed the stability of continuous spatiotemporal distributions of rice under stress, which can open up new avenues for identifying heavy metal stress in rice under complex stress conditions.

Purpose: This study aimed to investigate manifestations of the gastric wall and related risk factors in COVID-19 patients with gastrointestinal symptoms by CT. Materials and methods: Two hundred and forty patients diagnosed with COVID-19 by RT-PCR were enrolled from January 2020 to April 2020. Patients showed gastrointestinal symptoms, including nausea, vomiting, or diarrhea. Results of the initial laboratory examination were performed after admission. Chest CT was performed for all patients, with the lower bound including the gastric antrum. The volume of COVID-19 and lungs was segmented, and the ratio was calculated as follows: PV/LV = Volumepneumonia/Volumelungs. Results: Among the 240 patients, 109 presented with gastric wall edema (edema group), and 131 showed no gastric wall edema (non-edema group); the PV/LV values between the two groups were significantly different (P= 0.002). Univariate analysis revealed the following: fibrinogen (Fib), thrombin time (TT), activated partial thromboplastin time (APTT), and albumin (ALB) significantly differed between the two groups (P< 0.05). Binary logistic regression analysis showed that only APTT had a negative effect on gastric wall edema (P= 0.003). Conclusions: SARS-CoV-2 invades the gastrointestinal tract, gastric wall edema is the primary CT manifestation, and gastric wall edema is more likely to occur with a shorter APTT and severe pneumonia, with a slightly longer hospitalization time. Patients with gastric wall edema observed by CT should intervene early, which may improve digestive function, and further strengthen immune potency against COVID-19.

On August 15, 1962, an agreement was signed by the representatives of the Red Flag Canal users from two counties in China. Since then, it has enabled people from both counties to share canal benefits, and as such ably become a cornerstone for a peaceful canal culture between the two peoples. The agreement and its making process were both initiated by Yang Gui (杨贵), the top leader of one of the two counties who masterminded the Red Flag Canal project. In explaining his motivation, Yang Gui stated, “We are building the Red Flag Canal for posterity; we must do everything we can to save posterity the trouble.” However, just what“the trouble” he perceived was, whothe troublemaker he thought would be, and whyhe was confident that a bilateral agreement could serve the noble goal “to save posterity the trouble”, Yang Gui did not say, neither did he leave any record. In this article, we report our aspiration and endeavor to fill this knowledge gap, and present fresh discoveries and insights we derived from examining this instance through a CPR lens—an eclectic collection of economic constructs of common-pool resources (CPRs). The article is the fourth in a mini-series on the Red Flag Canal, one of the best kept secrets in the history of socio-ecological practice.

ABSTRACTSouthern China is a major rice-producing region where mixed rice cropping systems (single cropping rice (SCR) and double-cropping rice (DCR)) are widely practiced. An accurate estimation of the spatiotemporal changes in cropping systems is important for understanding the dynamic of paddy rice system and for developing suitable agricultural policies. However, few studies focus on mapping long-term changes in cropping systems in this subtropical region. The objective of this research is 1) to improve the phenology- and pixel-based paddy rice mapping (PPPM) algorithm by simultaneously considering the phenology signatures in the rice transplanting and heading periods; 2) to better identify different rice cropping systems and analyze their changes. Based on the improved PPPM method, we generated annual maps of SCR and DCR in southern China with image collection of Landsat 5, 7, and 8 from 1999 to 2019 using the Google Earth Engine platform. The overall accuracies of cropping system results for the study regions range from 81.0% to 98.1% depending on the areas of interest created in our study area. Then, the spatiotemporal patterns of the annual SCR and DCR time series were analyzed. In 2000, the total rice area was 208,614.6 km2, decreased sharply in 2003, and thereafter, the total increase in the paddy rice area fluctuated until 2011. From 2000 to 2019, the total rice area decreased to 171,474.3 km2in 2019. The results showed that relatively stable SCR mainly distributed in Anhui, Hubei, and Jiangsu provinces whereas DCR occurred in Guangdong, Hunan and Jiangxi provinces. DCR-to-SCR conversion occurred drastically in Hunan, Hubei, and Jiangxi provinces. Rice-to-non-rice conversion was more prevalent in Hunan and Hubei provinces. Detailed spatiotemporal information over 20 years suggested that the plans for agricultural resources utilization in some specific provinces should be proposed, which is of great significance for food security in the major rice-producing area in southern China.

Recently, the incidence of invasive fungal infections has significantly increased. Candida albicans (C. albicans)is the most common opportunistic fungal pathogen that infects humans. The limited number of available antifungal agents and the emergence of drug resistance pose difficulties to treatment, thus new antifungals are urgently needed. Through their functions in DNA replication, DNA repair and transcription, histone acetyltransferases (HATs) and histone deacetylases (HDACs) perform essential functions relating to growth, virulence, drug resistance and stress responses of C. albicans. Here, we summarize the physiological and pathological functions of HATs/HDACs, potential antifungal targets and underlying antifungal compounds that impact histone acetylation and deacetylation. We anticipate this review will stimulate the identification of new HAT/HDAC-related antifungal targets and antifungal agents.

Aim:To evaluate whether chelerythrine (CHT) exhibited antifungal activity against Candida albicans in vitroand in vivoand to explore the underlying mechanisms. Materials & methods:Broth microdilution assay and Galleria mellonellamodel were used to evaluate the antifungal effect in vitroand in vivo, respectively. Mechanism studies were investigated by morphogenesis observation, Fluo-3/AM, DCFH-DA and rhodamine6G assay, respectively. Results:CHT exhibited antifungal activity against C. albicansand preformed biofilms with minimum inhibitory concentrations ranged from 2 to 16 μg/ml. Besides, CHT protected G. mellonellalarvae infected by C. albicans. Mechanisms studies revealed that CHT inhibited hyphal growth, increased intracellular calcium concentration, induced accumulation of reactive oxygen species and inhibited drug transporter activity. Conclusion:CHT exhibited antifungal activity against C. albicans.

Microbial-assisted phytoremediation is of great significance for the remediation of soil contaminated with heavy metals (HMs). Probiotics are beneficial microorganisms that can improve soil structure and fertility and promote plant growth. This study aimed to investigate the effect of two kinds of probiotics, including Lactobacillus casei(L) and Bacillus licheniformis(B), on activating the remediation potentiality of leaf mustard [Brassica juncea(L.) Czerniak.] for mining soil contaminated by Cd and Zn. The results showed that addition of two probiotics significantly reduced soil pH (with 0.05–0.32 units) and improved the available contents of soil HMs (16.0%–59.9% for Cd and 7.1%–23.9% for Zn) in the indoor-incubation experiment. After probiotic treatments, available Cd and Zn in potting soil treated with 1×109cfu mL-1of B were 1.65-fold and 1.66-fold of the control, respectively.Meanwhile, soil alkaline phosphatase, urease and sucrose activities were increased, indicating that soil microbial metabolic activities were also motivated. Addition of L and B significantly improved the biomass and chlorophyll contents of leaf mustard. The contents of Cd, Zn in shoot and root were significantly increased with 1×105cfu mL-1of L treatment (shoot: 75.2%, 71.9%; root: 36.8%, 61.2%). Furthermore, the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and the level of malondialdehyde (MDA) were increased or inhibited, indicating that the resistance of plants to HMs was enhanced. These results indicated that two kinds of probiotics could improve the activities of Cd and Zn directly in mining soil and promote the growth of leaf mustard, thus increasing the efficiency of phytoremediation for HMs. The study provides a reference value for probiotic-assisted phytoremediation of soil contaminated with HMs.

Many reasons could lead to abnormal increased extraosseous tracer uptake on 99mTc-MDP bone scintigraphy. A 75-year-old man was referred a bone scintigraphy to evaluate his chest pain. The images revealed rib fractures. In addition, increased MDP activity in the muscle of the lower extremities was noted. The abnormal increased uptake in the muscles was likely related to the arterial thromboses revealed by vascular ultrasonography. The patient received interventional embolectomy.