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Object detection from UAV (unmanned aerial vehicle) images is a crucial and challenging task in the field of computer vision. The task suffers from the difficulties of small dense objects, low pixel occupation of objects, and features that are not easily extracted in images. In this paper, we proposed a multilayer feature fusion algorithm named SCA-YOLO (spatial and coordinate attention enhancement YOLO) for small object detection with hybrid attention mechanisms. It uses the single-stage detection algorithm YOLOv5 as the base framework. Firstly, a hybrid attention module with associated coordinate attention is designed to enhance the feature extraction of small objects. Secondly, to address the problem that small objects are vulnerable to being disturbed by the complex background information on UAV images, an improved SEB (simple and efficient bottleneck) module is designed to further distinguish foreground and background features. Thirdly, a multilayer feature fusion structure is built to perform channel stitching of shallow and deep feature maps, as well as to enrich the semantic information of shallow features by adding horizontal jump connections. Finally, experiments are conducted on the VisDrone2020 dataset, which involves a large number of small objects photographed by drones. In addition, we also conduct extended experiments on the DOTA dataset and PASCAL VOC dataset. Comparative experimental results indicate that the proposed method considerably improves the accuracy of small object detection on multiple benchmark datasets. [ABSTRACT FROM AUTHOR]

Human motion prediction aims to forecast future human poses given a historical motion. Current state-of-the-art approaches rely on deep learning architectures of arbitrary complexity, such as Recurrent Neural Networks (RNN), Graph Convolutional Networks (GCN), and typically requires multiple training stages and more parameters. In addition, existing learning-based methods fail to model the observation that human motion tends to repeat itself. In summary, to address the problem of the existing methods neglecting the repetitive nature of human motion, we first introduced a Multi-level Attention Mechanism (MAM) that explicitly leverages this observation to find relevant historical information for predicting future motion. Instead of modeling frame-wise attention via pose similarity, the motion attention was extracted to capture the similarity between the current motion context and the historical motion sub-sequences. In this context, the use of different types of attention, computed at joint, body part, and full pose levels was studied. Furthermore, to address the complexity of existing algorithms based on deep learning architectures, a Fully connected Transpose MLP (FTMLP) model was introduced. By combining a MLP network with a fully connected and transposed layer to process the aggregated relevant past movements, the patterns of motion from the long-term history can be quickly and efficiently used to predict the future poses. The experimental results on standard motion prediction benchmark datasets Human3.6 M and CMU motion capture dataset show that our model is able to make accurate short- and long-term predictions. [ABSTRACT FROM AUTHOR]

Vanadium (V) is an important heavy metal with ubiquitous presence in the Earth’s crust, but limited information is available as to its effect on plants and management strategies. Melatonin is a widely studied biomolecule; it acts as an antioxidant and a signaling molecule that enhances the abiotic stress tolerance of plants. Melatonin improves copper, zinc, and cadmium tolerance in plants. In this study, we investigated the response of watermelon seedlings to V stress and the potential role of melatonin in enhancing V stress tolerance of watermelon seedlings. The results showed that seedlings pretreated with melatonin (0.1 μM) exposed to V (50 mg/L) had a higher relative chlorophyll content (SPAD index), photosynthetic assimilation, and plant growth compared with non-melatonin pretreated seedlings. Melatonin pretreatment lowered leaf and stem V concentrations by reducing V transport from root to shoot. Melatonin pretreatment enhanced superoxide dismutase (SOD) and catalase (CAT) activities, and reduced the hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) content of watermelon seedlings, by regulating melatonin biosynthesis and gene expression for superoxide dismutase, peroxidase, ascorbate peroxidase, glutathione peroxidase, and glutathione S-transferase. So far as we know, these results are the first evidence that melatonin improves plant growth of watermelon seedlings under vanadium stress conditions. Considering these observations, melatonin can be utilized to reduce the availability of V to plants, and improve plant growth and V stress tolerance. [ABSTRACT FROM AUTHOR]

Background and aims : Magnesium (Mg) is an essential macronutrient that plays an important role in numerous physiological and biochemical processes of plant. However, Mg deficiency commonly occurs worldwide. Watermelon is an important crop that often suffers from Mg deficiency. This study aims to test whether watermelon performance can be improved by grafting onto rootstocks under low Mg and to clarify the underlying physiological mechanism. Methods : Self-grafted, bottle gourd (Jingxinzhen No.1) and pumpkin (Jingxinzhen No.4) rootstock-grafted plants were treated with three Mg concentrations: 2.0 mM (normal condition), 0.4 mM (moderate stress), and 0.04 mM (severe stress) for 16 days under hydroponic conditions. Ungrafted watermelon and pumpkin were treated with 2.0 mM and 0.04 mM for 12 days. Results : The growth of the plants was not affected by 0.4 mM Mg; however, plant growth decreased under 0.04 mM Mg in all graft combinations compared with control (2.0 mM Mg). Pumpkin rootstock grafting significantly increased watermelon growth under low Mg stress (0.04 mM Mg), compared with self-grafted and bottle gourd-grafted plants. The Mg uptake of watermelon plants was increased by grafting onto pumpkin rootstocks, however, root-to-shoot transport capacity of Mg was similar compared with self-grafted plants under 0.04 mM Mg. Gene expression analysis showed that magnesium transporter genes MGT1, MGT3, MGT4, and MGT5 may play an important role in higher Mg uptake of pumpkin root. The photosynthetic parameters and activities of superoxide dismutase, peroxidase and catalase were significantly higher, but malonaldehyde (MDA) content were lower in the pumpkin rootstock grafted plants compared with other graft combinations under 0.04 mM Mg. Conclusion : Our results provide strong evidence that pumpkin rootstock 'Jinxinzhen No. 4' grafting can improve watermelon performance under low Mg stress. The enhanced plant performance is attributed to higher root Mg uptake and the improvement of photosynthesis and antioxidant enzyme activities. [ABSTRACT FROM AUTHOR]

Biocultural diversity is an important result and outstanding representation of human-land relationship. This study established a novel framework for evaluating the coupling mechanism of biocultural diversity beyond the nature-culture dualism. Taking the Beichuan-River-Source National Nature Reserve (BRSNNR) as an example, combined with regional characteristics, Coupling Coordination Degree Model (CCDM) and Canonical Correlation Analysis (CCA) were used to explore the correlation mechanism between natural systems and cultural systems in protected areas. The research results indicated that BRSNNR had five types of landscape character areas with outstanding natural and cultural characteristics; the spatial distribution of biodiversity and cultural diversity was highly overlapping, forming a 'high-medium-low' three-level biocultural diversity area. Analysis demonstrated that positive or negative feedback patterns between natural and cultural systems contributed to the formation of representations of biocultural diversity. Altitude, animals, and traffic conditions are important drivers for the biological and cultural diversity in protected areas. At the same time, residents' emotions and behaviors have a direct impact on the formation of biocultural diversity. The research suggests that the priority protection areas and functional divisions of protected areas should be delineated according to the evaluation results of biocultural diversity, and thresholds should be calculated and set for the constraints. This method is conducive to the improvement of the system's ability to deal with risks and the formation of the action mechanism of 'factor interaction-system interaction-biocultural diversity representation' in protected areas. [ABSTRACT FROM AUTHOR]

Papillary thyroid cancer (PTC) is one of the most common cancers worldwide, and its carcinogenesis is influenced by a complex network of gene interactions. In this study, the microarray expression profile was re‐annotated into a lncRNA‐mRNA biphasic profile. LncRNA‐mRNA interactions were confirmed by established miRNA‐RNA data and hypergeometric test. Then, a PTC‐related lncRNA‐miRNA‐mRNA network (PTCRN) was constructed by integrating differentially expressed genes with the RNA‐RNA networks. The new network consisted of 21 lncRNAs, 241 mRNAs and 803 edges. To prioritize PTC‐related genes, we performed topological analysis and random walk with restart (PWR) algorithm analysis of PTCRN. Both analyses identified lncRNA RP11‐159F24.1 as a hub node in the network, which could interact with 47 mRNAs by sponging miR‐485. In functional enrichment analysis, these interacting mRNAs were associated with the pathways in cancer. In validation, RP11‐159F24.1 (up‐regulated; P = 0.0013) showed an opposite expression pattern with its target miR‐485 (down‐regulated; P = 0.0013) in PTC, indicating that the RP11‐159F24.1/miR‐485/mRNAs axis might play an important role in the development of PTC. In conclusion, this study has constructed a PTC‐related lncRNA‐miRNA‐mRNA network and identified the hub lncRNA RP11‐159F24.1 in the tumorigenesis, which provided novel insights to explore the underlying mechanism of PTC. This study has constructed a PTC‐related lncRNA‐miRNA‐mRNA network and identified the hub lncRNA RP11‐159F24.1 in the tumorigenesis, which provided novel insights to explore the underlying mechanism of PTC. [ABSTRACT FROM AUTHOR]

SUMMARY: In higher plants, the generation and release of viable pollen from anthers is vital for double fertilization and the initiation of seed development. Thus, the characterization of genes related to pollen development and anther dehiscence in plants is of great significance. The F‐box protein COI1 plays a crucial role in the jasmonate (JA) signaling pathway and interacts with many JAZ family proteins in the presence of jasmonoyl‐isoleucine (JA‐Ile) or coronatine (COR). The mutation of AtCOI1 in Arabidopsis leads to defective anther dehiscence and male sterility (MS), although COI has not been shown to affect fertility in Zea mays (maize). Here we identified two genes, ZmCOI2a and ZmCOI2b, that redundantly regulate gametophytic male fertility. Both ZmCOI2a and ZmCOI2b are highly homologous and constitutively expressed in all tissues tested. Subcellular localization revealed that ZmCOI2a and ZmCOI2b were located in the nucleus. The coi2a coi2b double mutant, generated by CRISPR/Cas9, had non‐dehiscent anthers, delayed anther development and MS. In addition, coi2a coi2b male gametes could not be transmitted to the next generation because of severe defects in pollen germination. The JA content of coi2a coi2b anthers was unaltered compared with those of the wild type, and the exogenous application of JA could not rescue the fertility defects of coi2a coi2b. Transcriptome analysis showed that the expression of genes involving the JA signaling transduction pathway, including ZmJAZ3, ZmJAZ4, ZmJAZ5 and ZmJAZ15, was affected in coi2a coi2b. However, yeast two‐hybrid assays showed that ZmJAZs interacted with ZmCOI1s, but not with ZmCOI2s. In conclusion, ZmCOI2a and ZmCOI2b redundantly regulate anther dehiscence and gametophytic male fertility in maize. Significance Statement: The F‐box protein COI1 plays a crucial role in the jasmonate signaling pathway. However, the function of COI in maize has remained elusive. Here, we identified two genes, ZmCOI2a and ZmCOI2b, that redundantly regulate anther dehiscence, filament elongation and gametophytic male fertility in maize. [ABSTRACT FROM AUTHOR]

To summarize, we demonstrate that I sldmp i mutants induce I in vivo i maternal haploids in a major dicot crop, tomato, and that identification of haploid embryos is facilitated by the FAST-Red marker. Keywords: tomato; doubled haploid technology; maternal haploid induction; genotype independent EN tomato doubled haploid technology maternal haploid induction genotype independent 250 252 3 01/17/22 20220201 NES 220201 Tomato ( I Solanum lycopersicon i ) is the second largest vegetable crop and the largest fruit crop (Costa and Heuvelink, 2018). Ploidy analysis of 218 putative haploid and 2303 putative diploid seedlings showed that FAST-Red can be used with 100% accuracy for selection of maternal haploids in tomato (Figure 1r). [Extracted from the article]

Grafting is a widely used technique in watermelon production. How grafting affects watermelon fruit yield and quality at low potassium supply and the mechanism remains unclear. This study addresses the question from agronomic, physiological and transcriptional perspective. Watermelon plants [ Citrullus lanatus (Thunb.) Matsum. and Nakai, cv. Zaojia 8424], either self-grafted or grafted onto the rootstock ‘Yongshi’ ( Citrullus lanatus sp.), ‘Jingxinzhen No.1’ ( Lagenaria siceraria Standl.), and ‘Qingyanzhen No.1’ ( Cucurbita maxima × C. moschata) . Plants were subjected to 6.0 mM K (normal K) and 0.1 mM K (low K). Compared with plants treated with 6.0 mM K, those supplied with 0.1 mM K produced less fruit yield as indicated by the decrease in single fruit weight of all plants; however, a smaller decrease was observed in plants grafted onto ‘Yongshi’ (10%), ‘Jingxinzhen No.1’ (15%) and ‘Qingyanzhen No.1’ (19%) than the self- grafted watermelon (38%). The K + concentration of stem, leaf, fruit peel and flesh were obviously higher in the rootstock- grafted plants than in the self- grafted ones under 0.1 mM K. In addition, rootstock- grafted plant had significantly higher leaf zeatin riboside and chlorophyll content. Fruit quality, including contents of total soluble solid, sucrose, vitamin C, lycopene, β-carotene, were significantly decreased in the self- grafted plants under 0.1 mM K. However, 0.1 mM K treatment did not result in an obvious decrease in most of the measured fruit quality parameters in the rootstock- grafted plants. Fruit transcriptome analysis showed that there were 670, 27, 16 and 15 differential expressed genes (DGEs) responded to 0.1 mM K in the self- grafted, ‘Yongshi’, ‘Jingxinzhen No.1’ and ‘Qingyanzhen No.1’- grafted plants, respectively, indicating that rootstock grafting decrease the sensitivity of watermelon fruit to 0.1 mM K at the transcriptome level, GO and KEGG analysis showed that most of the DGEs were enriched in cellular metabolic process and metabolic pathways. Low K (0.1 mM K) significantly increased the gene expression of potassium channel ( Cla020934 ), but decreased the gene expression of phytoene synthase ( Cla009122- responsible for lycopene synthesis) in the fruit flesh of self-grafted watermelon. Taken together, the above results suggested that compared with self- grafted plants, watermelon grafted onto rootstock can enhance plant fruit yield, quality and decrease the sensitivity of fruit flesh transcriptome to low K. The mechanism of improved performance under low potassium is discussed. [ABSTRACT FROM AUTHOR]