Search

EEG pattern recognition is an important part of motor imagery- (MI-) based brain computer interface (BCI) system. Traditional EEG pattern recognition algorithm usually includes two steps, namely, feature extraction and feature classification. In feature extraction, common spatial pattern (CSP) is one of the most frequently used algorithms. However, in order to extract the optimal CSP features, prior knowledge and complex parameter adjustment are often required. Convolutional neural network (CNN) is one of the most popular deep learning models at present. Within CNN, feature learning and pattern classification are carried out simultaneously during the procedure of iterative updating of network parameters; thus, it can remove the complicated manual feature engineering. In this paper, we propose a novel deep learning methodology which can be used for spatial-frequency feature learning and classification of motor imagery EEG. Specifically, a multilayer CNN model is designed according to the spatial-frequency characteristics of MI EEG signals. An experimental study is carried out on two MI EEG datasets (BCI competition III dataset IVa and a self-collected right index finger MI dataset) to validate the effectiveness of our algorithm in comparison with several closely related competing methods. Superior classification performance indicates that our proposed method is a promising pattern recognition algorithm for MI-based BCI system. [ABSTRACT FROM AUTHOR]

Motor imagery (MI) tasks evoke event-related desynchronization (ERD) and synchronization (ERS); the ERD-/ERS-related features appearing at specific channels are frequency and time localized. Therefore, optimal channels, frequency band and time interval are of great significance for MI electroencephalography feature extraction. In this paper, channel selection method based on linear discriminant criteria is used to automatically select the channels with high discriminative powers. In addition, the concept of artificial bee colony algorithm is first introduced to find the global optimal combination of frequency band and time interval simultaneously without prior knowledge for common spatial pattern features extraction and classification. Experimental results demonstrate that this scheme can adapt to user-specific patterns and find the relatively optimal channels, frequency band and time interval for feature extraction. The classification results on the BCI Competition III Dataset IVa and BCI Competition IV Dataset IIa clearly present the effectiveness of the proposed method outperforming most of the other competing methods in the literature. [ABSTRACT FROM AUTHOR]

Effective feature extraction and classification methods are of great importance for motor imagery (MI)-based brain-computer interface (BCI) systems. The common spatial pattern (CSP) algorithm is a widely used feature extraction method for MI-based BCIs. In this work, we propose a novel spatial-frequency-temporal optimized feature sparse representation-based classification method. Optimal channels are selected based on relative entropy criteria. Significant CSP features on frequency-temporal domains are selected automatically to generate a column vector for sparse representation-based classification (SRC). We analyzed the performance of the new method on two public EEG datasets, namely BCI competition III dataset IVa which has five subjects and BCI competition IV dataset IIb which has nine subjects. Compared to the performance offered by the existing SRC method, the proposed method achieves average classification accuracy improvements of 21.568 and 14.38% for BCI competition III dataset IVa and BCI competition IV dataset IIb, respectively. Furthermore, our approach also shows better classification performance when compared to other competing methods for both datasets. [ABSTRACT FROM AUTHOR]

Background Common spatial pattern (CSP) is most widely used in motor imagery based brain-computer interface (BCI) systems. In conventional CSP algorithm, pairs of the eigenvectors corresponding to both extreme eigenvalues are selected to construct the optimal spatial filter. In addition, an appropriate selection of subject-specific time segments and frequency bands plays an important role in its successful application. New method This study proposes to optimize spatial-frequency-temporal patterns for discriminative feature extraction. Spatial optimization is implemented by channel selection and finding discriminative spatial filters adaptively on each time-frequency segment. A novel Discernibility of Feature Sets (DFS) criteria is designed for spatial filter optimization. Besides, discriminative features located in multiple time-frequency segments are selected automatically by the proposed sparse time-frequency segment common spatial pattern (STFSCSP) method which exploits sparse regression for significant features selection. Finally, a weight determined by the sparse coefficient is assigned for each selected CSP feature and we propose a Weighted Naïve Bayesian Classifier (WNBC) for classification. Results Experimental results on two public EEG datasets demonstrate that optimizing spatial-frequency-temporal patterns in a data-driven manner for discriminative feature extraction greatly improves the classification performance. Comparison with existing methods The proposed method gives significantly better classification accuracies in comparison with several competing methods in the literature. Conclusions The proposed approach is a promising candidate for future BCI systems. [ABSTRACT FROM AUTHOR]

Summary: A cold-tolerant line (NY-1) and a cold-sensitive cultivar (Jinyan 4) of cucumber (Cucumis sativus) were treated with temperatures of 28°C/22°C or 28°C/12°C (day/night) in a 10-h photoperiod. Carbohydrates and related enzymes were assayed from 0 to 4h after the start of the dark period. Compared to the normal night temperature (22°C, control), sucrose, stachyose and galactinol increased in mature leaves under cold-night treatment (12°C) while sucrose, glucose and fructose in fruits remained unchanged. In peduncles, where stachyose is catabolized to sucrose after long-distance transport, cold nights simultaneously induced a significant increase of stachyose (substrate) and a decrease of sucrose (product), indicating that the metabolic step from stachyose to sucrose in peduncles is crucial to translocation inhibition in cold nights. This decrease was more pronounced in the cold-sensitive cultivar. Similar growth rates of fruits on one-fruit and two-fruit plants under cold-night treatment further confirmed that it is sink activity rather than source supply that is limiting the source–sink translocation. No significant genotypic differences in enzyme activities involved in the stachyose–sucrose conversion, including alkaline α-galactosidase, acid α-galactosidase, galactokinase, uridine diphosphate (UDP)-galactose pyrophosphorylase, UDP–glucose-4′-epimerase and sucrose synthase, were observed when assayed in an adenosine triphosphate (ATP)-rich in vitro environment. However, the ATP concentration was much higher in peduncles of the cold-tolerant line, indicating that a limiting ATP supply may be partially responsible for the stronger inhibition of the stachyose–sucrose pathway observed in the cold-sensitive cultivar (Jinyan 4). [Copyright &y& Elsevier]

Pumpkin (Cucurbita maxima) is an important vegetable crop of the Cucurbitaceae plant family. The fruits of pumpkin are often used as directly edible food or raw material for a number of processed foods. In nature, mature pumpkin fruits differ in size, shape, and color. The Atlantic Giant (AG) cultivar has the world's largest fruits and is described as the giant pumpkin. AG is well-known for its large and bright-colored fruits with high ornamental and economic value. At present, there are insufficient studies that have focused on the formation factors of the AG cultivar. To address these knowledge gaps, we performed comparative transcriptome, proteome, and metabolome analysis of fruits from the AG cultivar and a pumpkin with relatively small fruit (Hubbard). The results indicate that up-regulation of gene-encoded expansins contributed to fruit cell expansion, and the increased presence of photoassimilates (stachyose and D-glucose) and jasmonic acid (JA) accumulation worked together in terms of the formation of large fruit in the AG cultivar. Notably, perhaps due to the rapid transport of photoassimilates, abundant stachyose that was not converted into glucose in time was detected in giant pumpkin fruits, implying that a unique mode of assimilate unloading is in existence in the AG cultivar. The potential molecular regulatory network of photoassimilate metabolism closely related to pumpkin fruit expansion was also investigated, finding that three MYB transcription factors, namely CmaCh02G015900, CmaCh01G018100, and CmaCh06G011110, may be involved in metabolic regulation. In addition, neoxanthin (a type of carotenoid) exhibited decreased accumulation that was attributed to the down-regulation of carotenoid biosynthesis genes in AG fruits, which may lead to pigmentation differences between the two pumpkin cultivars. Our current work will provide new insights into the potential formation factors of giant pumpkins for further systematic elucidation. [ABSTRACT FROM AUTHOR]

Removing senescent leaves is vital for boosting greenhouse tomato yield. This study suggests utilising sucrose concentrations in tomato petiole ends as an indicator for assessing leaf senescence. Sucrose concentrations in different leaf positions were analysed during fruiting, pre-harvesting, and harvesting periods. Leaf area and photosynthetically active radiation (PAR) data from tomato plants were input into tomato photosynthesis and respiration models simulating the yield for each compound leaf. The hyperspectral technique enabled rapid and non-destructive determination of sucrose concentration in tomato petioles using a portable spectroradiometer (ASD Fieldspec® 3) that measured spectral reflectance in 120 petiole samples. Raw spectral reflectance underwent various pretreatments. Principal component analysis (PCA) reduced data dimensions, and sucrose-spectral quantitative prediction models were established using support vector regression (SVR), k-nearest neighbour (KNN), and partial least squares (PLS). The best model for sucrose-spectral quantitative prediction was obtained by moving average (MA) preprocessing, PCA dimensionality reduction and PLS algorithm, resulting in determination coefficient of prediction set (Rp2) of 0.98 and residual predictive deviation (RPD) of 7.12. Sucrose quantitative prediction and photosynthetic respiration models exhibited a parallel trend, with assimilation capacity increasing and then decreasing with leaf position, indicating that functional leaves produce the most assimilates. Young leaves, being immature, produce limited assimilates. Despite well-developed senescent leaves, the occlusion by upper leaves hinders the release of photosynthetic potential, resulting in negative net assimilates. These findings provide compelling evidence that spectroscopy can quantitatively predict sucrose concentration in tomato petioles, aiding in effective senescent leaf identification. [Display omitted] • A quantitative relationship between spectral reflectance and sucrose was build. • Identifying senescent leaf by measuring sucrose content in tomato petioles. • Net leaf assimilation validate the senescent leaf identification criterion. [ABSTRACT FROM AUTHOR]

Straw mulching on wet beds is an effective method to alleviate continuous cropping obstacles in greenhouses. However, this technique cannot be applied in the production of leafy vegetables with high planting density. Straw mulching in furrows is an alternative method in this circumstance. In this study, celery (Apium graveolens L.), a vegetable that prefers a high planting density and wet soil, was used to test furrow straw mulching technology, and the effect of different straw amounts and straw decomposers on soil improvement and celery production was investigated. The results showed that straw mulching in furrows significantly reduced soil conductivity and nitrate nitrogen levels, increased the contents of soil organic carbon as well as phosphorus and potassium nutrients in the bed, and improved celery yield and quality, indicating the significant lateral movement of released nutrients between the furrow and bed. The positive effects of 15,000 kg/ha straw application were more pronounced than those of 7500 kg/ha and 11,250 kg/ha. In addition, straw decomposers accelerated nutrient release and improved celery yield and quality. A decomposer named "ZhuBang" containing Bacillus licheniformis was the most effective. We concluded that furrow straw mulching combined with straw decomposer application is an effective measure for the sustainable production of leafy vegetables in intensive vegetable production facilities. [ABSTRACT FROM AUTHOR]

Invertases and their inhibitors play important roles in sucrose metabolism, growth and development, signal transduction, and biotic and abiotic stress tolerance in many plant species. However, in cucumber, both the gene members and functions of invertase and its inhibitor families remain largely unclear. In this study, in comparison with the orthologues of Citrullus lanatus (watermelon), Cucumis melo (melon), and Arabidopsis thaliana (Arabidopsis), 12 invertase genes and 12 invertase inhibitor genes were identified from the genome of Cucumis sativus (cucumber). Among them, the 12 invertase genes were classified as 4 cell wall invertases, 6 cytoplasmic invertases, and 2 vacuolar invertases. Most invertase genes were conserved in cucumber, melon, and watermelon, with several duplicate genes in melon and watermelon. Transcriptome analysis distinguished these genes into various expression patterns, which included genes CsaV3_2G025540 and CsaV3_2G007220, which were significantly expressed in different tissues, organs, and development stages, and genes CsaV3_7G034730 and CsaV3_5G005910, which might be involved in biotic and abiotic stress. Six genes were further validated in cucumber based on quantitative real-time PCR (qRT–PCR), and three of them showed consistent expression patterns as revealed in the transcriptome. These results provide important information for further studies on the physiological functions of cucumber invertases (CSINVs) and their inhibitors (CSINHs). [ABSTRACT FROM AUTHOR]

Soil is the base for conventional plant growth. The rhizosphere pressure generated from soil compaction shows a dual effect on plant growth in agricultural production. Compacted soil leads to root growth stagnation and causes bending or thickening, thus affecting the growth of aboveground parts of plants. In arrowhead (Sagittaria trifolia L.), the corms derived from the expanded tips of underground stolons are its storage organ. We found that the formation of corms was significantly delayed under hydroponic conditions without rhizosphere pressure originating from soil/sand. In the initial stage of corm expansion, the anatomic structure of arrowhead corm-forming parts harvested from hydroponics and sand culture was observed, and we found that the corm expansion was derived from cell enlargement and starch accumulation. Comparative transcriptome analysis indicated that the corm expansion was closely related to the change in endogenous hormone levels. Endogenous abscisic acid and salicylic acid concentrations were significantly increased in sand-cultured corms. Higher ethylene and jasmonic acid contents were also detected in all arrowhead samples, demonstrating that these hormones may play potential roles in the rhizosphere pressure response and corm expansion. The expression of genes participating in hormone signaling could explain the rising accumulation of certain hormones. Our current results draw an extensive model to reveal the potential regulation mechanism of arrowhead corm expansion promoted by rhizosphere pressure, which will provide important references for further studying the molecular mechanism of rhizosphere pressure modulating the development of underground storage organs in other plants. [ABSTRACT FROM AUTHOR]

To pursue high yields, the excessive application of nitrogen (N) fertilizer has been reported in high-residual soil nitrate levels, excessive nitrate leaching, and nitrate contamination of groundwater. In this study, tomato crops (Lycopersicon esculentum Mill.) were subjected to various nitrogen treatments, and the nitrate nitrogen content, soil water content at different soil layers, dry matter, and yield were measured. A mechanistic model, EU-Rotate_N, was used to simulate the aforementioned indexes in a region of Jiangsu province with a relatively higher water table. The predicted values of soil moisture and soil nitrate content at various soil depths agree well with the measured values during tomato growth. The statistical index of soil water content ranged from 0.367 to 0.749, 0.856 to 0.947, and the statistical index of soil nitrate nitrogen content ranged from 0.365 to 0.698, and 0.869 to 0.932, for Autumn-Winter (AW) and Spring-Summer (SS) crops, respectively. Moreover, the dry weight and yield simulation effects of the tomato are also in good agreement with the actual measured values. The results show that the EU-Rotate_N model is effective in simulating soil water content, nitrate nitrogen content, dry matter quality, and yield in Jiangsu province, with little underestimation in soil water content at a soil depth of 20–30 cm during SS, which might be improved further considering the high water table of the region. [ABSTRACT FROM AUTHOR]

Real-time quantitative PCR (RT-qPCR) is a method with high sensitivity and convenience that has been extensively used to analyze the expression level of target genes. A reference gene with a highly stable expression is required to ensure the accuracy of experimental results. However, the report on appropriate reference genes in arrowheads (Sagittaria trifolia) is still limited. In this study, eight candidate reference genes (ACT5, UBQ, GAPDH, CYP, NAC, IDH, SLEEPER and PLA) were selected. The candidate genes were employed in a RT-qPCR assay in different tissues at different developmental stages of the same tissue (including corm, leaf and leafstalk) in arrowheads. Five statistical algorithms, GeNorm, NormFinder, BestKeeper, delta cycle threshold (ΔCt) and RefFinder, were used to evaluate the stability of these genes' expressions in order to identify the appropriate reference genes. The results showed that UBQ was the optimum reference gene in leaf, leafstalk, root, stolon and corm, IDH exhibited the most stable expression during the expansion of corm, UBQ and PLA were the most stable reference genes in developmental stages of leaf and leafstalk, respectively. Finally, the reliability of reference genes was further confirmed by the normalization of PDS and EXP1 genes under different arrowhead tissues and developmental stages of corm, respectively. This study constitutes important guidance for the selection of reliable reference genes for analyzing the tissue- and developmental-stage-specific expression of genes in arrowheads. [ABSTRACT FROM AUTHOR]

MADS-box genes are important transcription factors in eukaryotes that are involved in regulating the growth and development of many plants. Jiaobai is a special aquatic vegetable formed through the stem expansion of Zizania latifolia infected by Ustilago esculenta and is wildly cultivated in Southeast Asia. To date, the biological function of MADS-box genes in Z. latifolia remains largely unknown. In this study, a genome-wide search for MADS-box genes in Z. latifolia was performed, and 87 MADS-box genes were identified. According to the phylogenetic analysis, there were 27 type I genes and 60 type II genes. The type I genes were mainly distributed in the Mα, Mβ and Mγ subfamilies, and the type II genes were divided into 14 subfamilies and unevenly distributed across 17 chromosomes. The encoded protein sequences ranged from 91 to 433 amino acids, the number of exons was 1~14, and most type I genes did not contain introns. The promoter region contained a large number of functional domains related to light response, plant hormones, stress and the meristem. An analysis of the expression patterns showed that there were massive differences in the expression of the MADS-box genes in different tissues, with six genes highly expressed in leaves and eight genes highly expressed in the stem apical meristem. Photoperiod and temperature were found to regulate the formation of the stem gall (SG) of Z. latifolia, and short-day (SD) conditions had an obvious promoting effect. ZlMADS57 and ZlMADS85 were significantly increased in SG under SD. Further analysis of the expression levels of MADS-box genes during the developmental stages of Z. latifolia found that the ZlMADS45, ZlMADS57, ZlMADS81 and ZlMADS85 were highly expressed 10 days before the SG formation, and ZlMADS66 reached its highest value on the day when the SG began forming. ZlMADS14, ZlMADS15, ZlMADS32, ZlMADS36, ZlMADS59 and ZlMADS71 were highly expressed after SG expansion, indicating that the MADS-box gene may play an important role in regulating SG formation and the subsequent expansion of Jiaobai. This study provides a reference for the functional identification of the MADS-box gene family and establishes a foundation for regulating the maturity of Z. latifolia. [ABSTRACT FROM AUTHOR]

Photosynthate partitioning between source and sink is a key determinant of crop yield. In contrast to sucrose-transporting plants, cucumber (Cucumis sativus) plants mainly transport stachyose and stachyose synthase (CsSTS) synthesizes stachyose in the vasculature for loading. Therefore, CsSTS is considered a key regulator of carbon partitioning. We found that CsSTS expression and CsSTS enzyme activity were upregulated in the vasculature and downregulated in mesophyll tissues at fruiting. In situ hybridization and tissue enrichment experiments revealed that a cis-natural antisense noncoding transcript of CsSTS, named asCsSTS, is mainly expressed in mesophyll tissues. In vitro overexpression (OE), RNA interference (RNAi), and dual luciferase reporter experiments indicated that CsSTSs are negatively regulated by asCsSTS. Fluorescence in situ hybridization revealed that asCsSTS transcript localized in leaf cytoplasm, indicating that the regulation of CsSTS by asCsSTS is a posttranscriptional process. Further investigation revealed that this regulation occurred by reducing CsSTS transcript stability through a DICER-like protein-mediated pathway. Chemically induced OE and RNAi of asCsSTS led to promotion or inhibition, respectively, of assimilate export from leaves and altered fruit growth rates. Our results suggest that the regulation of CsSTSs between the mesophyll and vasculature reduces sugar storage in mesophyll tissue and promotes assimilate export from the leaf when the plant carries fruit. The expression of Stachyose synthase is post-transcriptionally modulated by the antisense long noncoding RNA asCsSTS and this balance regulates assimilate export from leaves and fruit growth rates. [ABSTRACT FROM AUTHOR]

WD40 proteins, a super gene family in eukaryotes, are involved in multiple biological processes. Members of this family have been identified in several plants and shown to play key roles in various development processes, including acting as scaffolding molecules with other proteins. However, WD40 proteins have not yet been systematically analyzed and identified in Cucurbita maxima. In this study, 231 WD40 proteins (CmWD40s) were identified in C. maxima and classified into five clusters. Eleven subfamilies were identified based on different conserved motifs and gene structures. The CmWD40 genes were distributed in 20 chromosomes; 5 and 33 pairs of CmWD40s were distinguished as tandem and segmental duplications, respectively. Overall, 58 pairs of orthologous WD40 genes in C. maxima and Arabidopsis thaliana, and 56 pairs of orthologous WD40 genes in C. maxima and Cucumis sativus were matched. Numerous CmWD40s had diverse expression patterns in fruits, leaf, stem, and root. Several genes were involved in responses to NaCl. The expression pattern of CmWD40s suggested their key role in fruit development and abiotic stress response. Finally, we identified 14 genes which might be involved in fruit development. Our results provide valuable basis for further functional verification of CmWD40s in C. maxima. [ABSTRACT FROM AUTHOR]

In recent years, a lot of excellent multi-view clustering methods have been proposed. Because most of them need to fuse all views at one time, they are infeasible as the number of views increases over time. If the present multi-view clustering methods are employed directly to re-fuse all views at each time, it is too expensive to store all historical views. In this paper, we proposed an efficient incremental multi-view spectral clustering method with sparse and connected graph learning (SCGL). In our method, only one consensus similarity matrix is stored to represent the structural information of all historical views. Once the newly collected view is available, the consensus similarity matrix is reconstructed by learning from its previous version and the current new view. To further improve the incremental multi-view clustering performance, the sparse graph learning and the connected graph learning are integrated into our model, which can not only reduce the noises, but also preserve the correct connections within clusters. Experiments on several multi-view datasets demonstrate that our method is superior to traditional methods in clustering accuracy, and is more suitable to deal with the multi-view clustering with the number of views increasing over time. [ABSTRACT FROM AUTHOR]

Network reliability plays an important role in analysis, synthesis and detection of real-world networks. In this paper, we first propose the concept of hypernetwork reliability, which generalizes the concept of network reliability. The model for hypernetwork reliability studies consists of a hypergraph with perfect reliable vertices and equal and independent hyperedge failure probability 1 − p. The measure of reliability is defined as the probability that a hypergraph is connected. Let H be an r -uniform hypergraph with the number of vertices n and the number of hyperedges m , where every hyperedge connects r vertices. We confirm the possibility of the existence of a fixed hypergraph that is optimal or least for all hyperedges same survival possible p. It is simple to verify that such hypergraph exists if m = [ n − 1 r − 1 ]. For a kind of 2-regular 3-uniform hypergraphs, we calculate the upper and lower bounds on the all-terminal reliability, and describe the class of hypergraphs that reach the boundary. [ABSTRACT FROM AUTHOR]

Overapplication of nitrogen fertilizer and water in vegetable production is popular and serious in China and other developing countries, leading to severe environmental pollution. To date, most model-based decision support systems, which are believed to be powerful tools for improving fertilizer and water management in vegetable production, have been established by developed countries, and the weather, soil, hydrology, facility type and vegetable species of developing countries have been less considered. In this study, a water level component and a new vegetable species, pakchoi (Brassica campestris ssp. Chinese) were incorporated into EU-Rotate_N, a simulation model developed by the European Union for open field vegetable cultivation. The experiment was carried out in typical vegetable plastic tunnels in Jiangsu Province, China, an area with high groundwater level. The results indicated that the water level algorithm which differentiate the soil into saturated and unsaturated layers enhanced the model simulation accuracy of the soil nitrogen and water content in the 30 cm soil layer, indicating the significant influence of groundwater on the soil water and nutrient movement. The pakchoi experiment suggest that new vegetables could be added into the crop list of EU-Rotate_N by adjusting parameters with 'trial and error' methods after considering its biological characteristics. Furthermore, a novel module was added for recommendations of fertilization and irrigation on daily basis in accordance with reasonable upper and lower thresholds of soil water content and soil available nitrogen after a series of adjustment. Finally, a user-friendly application (APP) was developed based on the improved model. The evaluation experiments in 2021 and 2022 showed that APP could significantly improve nitrogen and water use efficiency without obvious yield loss in pakchoi production. We conclude that simulation models for vegetable fertilizer and water management established by developed countries could be modified by several operable steps to expand its application area. • An algorithm was added in EU-Rotate_N and its performance in high groundwater level was improved. • New vegetable pakchoi was successfully added, indicating crop scopes of the model can be expanded. • A user-friendly APP that support multiple users was developed with daily fertilization and irrigation recommendations. [ABSTRACT FROM AUTHOR]

Highlights • Shallow groundwater had a considerable contribution on cucumber evapotranspiration. • In this condition 75% of estimated cucumber ETc optimize cucumber yield. • Using fertigation, 75% of the traditionally recommended N optimize cucumber yield. • Frequent irrigation with low water volume is important when water table is high. Abstract The middle and lower reaches of Yangtze River present high rainfall and always have a high water table. Recently drip fertigation has been introduced and widely used for vegetable production in this area. To investigate the effect of shallow groundwater and the newly-developed fertigation on the cucumber water and nitrogen (N) requirement, experiments were carried out in plastic tunnels in Yangzhou, Jiangsu, China, during the 2016 and 2017 growing seasons using a randomized block design with three replicates. Four N rates, 4 irrigation amounts and 2 irrigation intervals (2 d and 4 d) were applied in this experiment. The results showed that irrigation amount of 75% of estimated plant evapotranspiration (ET c) was optimal to obtain the highest yield, indicating shallow groundwater had a considerable contribution to the cucumber plant evapotranspiration in this condition. Fertigation technology improved the irrigation water use efficiency (IWUE) and N use efficiency (NUE) and 75% of the recommended N rate (calculated according to a traditional local nutrient balance method) optimized cucumber yield. Frequent irrigation with low water volume had a beneficial impact on the improvement of cucumber yield, IWUE, NUE and reduced the N leaching. According to this work, the recommended fertigation strategy is 0.75 of recommended N, 0.75 estimated ET c and 2 d irrigation interval in this experiment, in which cucumber yield of 105.4 Mg ha−1, IWUE of 41.1 kg m-3 and NUE of 356.4 kg kg−1 were achieved. [ABSTRACT FROM AUTHOR]

Raffinose family oligosaccharides (RFOs) accumulate under stress conditions in many plants and have been suggested to act as stress protectants. To elucidate the metabolic process of RFOs under cold stress, levels of RFOs, and related carbohydrates, the expression and activities of main metabolic enzymes and their subcellular compartments were investigated during low-temperature treatment and during the recovery period in cucumber leaves. Cold stress induced the accumulation of stachyose in vacuoles, galactinol in vacuoles and cytosol, and sucrose and raffinose in vacuoles, cytosol, and chloroplasts. After cold stress removal, levels of these sugars decreased gradually in the respective compartments. Among four galactinol synthase genes ( CsGS ), CsGS1 was not affected by cold stress, while the other three CsGSs were up-regulated by low temperature. RNA levels of acid-α-galactosidase ( GAL ) 3 and alkaline-α-galactosidase ( AGA) 2 and 3 , and the activities of GAL and AGA, were up-regulated after cold stress removal. GAL3 protein and GAL activity were exclusively located in vacuoles, whereas AGA2 and AGA 3 proteins were found in cytosol and chloroplasts, respectively. The results indicate that RFOs, which accumulated during cold stress in different subcellular compartments in cucumber leaves, could be catabolized in situ by different galactosidases after stress removal. [ABSTRACT FROM AUTHOR]

Background/Aims: Our study aims to investigate the role, effect and mechanisms of ESRP1 (epithelial splicing regulatory protein 1) in epithelial-mesenchymal transition (EMT) in epithelial ovarian cancer (EOC). Methods: Microarray and immunohistochemical analysis of ESRP1 expression were performed in EOC cases. The correlations between ESRP1 expression and clinical factors on EOC were assessed. Lentivirus-mediated RNA interference and EGFP vector which contains ESRP1 gene were used to down-regulate and up-regulate ESRP1 expression in human EOC cell lines. Roles of ESRP1 in cell growth, migration and invasion of EOC cells were also measured by Cell Counting Kit-8 and Transwell systems in vitro and by a nude mice intraperitoneal transplantation model in vivo. Results: By the analysis of Gene Expression Omnibus (GEO) (p<0.05) and our own microarray data (p<0.001), ESRP1 expression in EOC was significantly different from normal ovarian tissue. It was abundant in the nuclei of cancer cells and in malignant lesions. However, it was weakly expressed or negative in both normal and benign lesions. High ESRP1 expression in EOC was associated with poor clinical outcomes. Decreased ESRP1 expression significantly increased cell migration and invasion both in vivo and in vitro. Snail strongly repressed ESRP1 transcription through binding to the ESRP1 promoter in EOC cells. Furthermore, ESRP1 regulated the expression of CD44s. Down-regulated ESRP1 resulted in an isoform switching from CD44v to CD44s, which modulated epithelial-mesenchymal transition (EMT) program in EOC. Up-regulatin of ESRP1 was detected in mesenchymal to epithelial transition (MET) in vivo. Conclusions: ESRP1 regulates CD44 alternative splicing during the EMT process which plays an important role in EOC carcinogenesis. In addition, ESRP1 is associated with disease prognosis in EOC. [ABSTRACT FROM AUTHOR]

In cucumber ( Cucumis sativus L.), the preexisting fruits inhibit the growth of subsequent fruits. To study the mechanism underlying this phenomenon, we examined the sink activity, the level of free sugars, and the activity of SNF1-related protein kinase 1 (SnRK1) in the peduncles of two types of fruits. In the two-fruit cucumber plants, the growth rate and sink activity [evaluated by alkaline alpha-galactosidase (CsAGA) activity in the peduncle] of the first fruit were greater than those of the second fruit. The 14 C-labeling experiment revealed that assimilates produced by the leaves closer to the second fruit tended to move to the first fruit. Sucrose and trehalose-6-phosphate (T6P) levels in the peduncle of the first fruit were higher than those in the peduncle of the second fruit. The SnRK1 activity was lower in the peduncle of the first fruit than in that of the second fruit at 0–8 days after anthesis. The growth rate and sink activity of the second fruit were enhanced after the removal of the first fruit or after treatment with 6-benzyl aminopurine, as determined by comparison with an increase in the sucrose and T6P levels and a decrease in the SnRK1 activity in its peduncle. The SnRK1 activity was inhibited by T6P in an in vitro kinase assay, and the mRNA level of CsAGA1 in cucumber calli was up-regulated by exogenous trehalose treatment, confirming that the SnRK1 activity and CsAGA1 expression can be regulated by T6P levels. Our results suggest that the T6P- and SnRK1-mediated signaling functions are involved in the regulation of first-fruit inhibition in cucumber plants. [ABSTRACT FROM AUTHOR]

The rational use of a large amount of straw produced from grain fields is an important issue in major grain-producing areas. On the other hand, due to the long-term preferential applications of chemical fertilizers, soil organic carbon (SOC) content, soil fertility and organic matter levels have decreased, and the soil physical-chemical properties have deteriorated in protected agricultural facilities. In this study, a wet crop, taro (Colocasia esculenta (L.) Schott) and the straw of two main crops [wheat (Triticum aestivum L.) and rice (Oryza sativa L.)] were selected to investigate the effect of row-surface straw mulching on taro yields and soil chemical properties. The results showed that nearly all wheat straw and 74% of rice straw decomposed in one season under wet conditions. Straw mulching significantly increased the taro yield, increased the levels of SOC, soil rapid available nitrogen, phosphorus and potassium, and improved the activities of sucrase and phosphatase in the soil. We conclude that row-surface straw mulching t of wet crops could not only improve the soil properties and crop yields in the protected facility but could also consume considerable straw (wheat: 14,250 kg/ha, rice: 111,00 kg/ha), and the method applied in other areas with similar conditions. [ABSTRACT FROM AUTHOR]

The controlling of robotic arms based on brain–computer interface (BCI) can revolutionize the quality of life and living conditions for individuals with physical disabilities. Invasive electroencephalography (EEG)-based BCI has been able to control multiple degrees of freedom (DOFs) robotic arms in three dimensions. However, it is still hard to control a multi-DOF robotic arm to reach and grasp the desired target accurately in complex three-dimensional (3D) space by a noninvasive system mainly due to the limitation of EEG decoding performance. In this study, we propose a noninvasive EEG-based BCI for a robotic arm control system that enables users to complete multitarget reach and grasp tasks and avoid obstacles by hybrid control. The results obtained from seven subjects demonstrated that motor imagery (MI) training could modulate brain rhythms, and six of them completed the online tasks using the hybrid-control-based robotic arm system. The proposed system shows effective performance due to the combination of MI-based EEG, computer vision, gaze detection, and partially autonomous guidance, which drastically improve the accuracy of online tasks and reduce the brain burden caused by long-term mental activities. [ABSTRACT FROM AUTHOR]

A Raffinose family oligosaccharides (RFOs) is one of the major translocated sugars in the vascular bundle of cucumber, but little RFOs can be detected in fruits. Alpha-galactosidases (α-Gals) catalyze the first catabolism step of RFOs. Six α-Gal genes exist in a cucumber genome, but their spatial functions in fruits remain unclear. Here, we found that RFOs were highly accumulated in vascular tissues. In phloem sap, the stachyose and raffinose content was gradually decreased, whereas the content of sucrose, glucose and fructose was increased from pedicel to fruit top. Three alkaline forms instead of acid forms of α-Gals were preferentially expressed in fruit vascular tissues and alkaline forms have stronger RFO-hydrolysing activity than acid forms. By inducible gene silencing of three alkaline forms of α-Gals, stachyose was highly accumulated in RNAi-CsAGA2 plants, while raffinose and stachyose were highly accumulated in RNAi-CsAGA1 plants. The content of sucrose, glucose and fructose was decreased in both RNAi-CsAGA1 and RNAi-CsAGA2 plants after β-estradiol treatment. In addition, the fresh- and dry-weight of fruits were significantly decreased in RNAi-CsAGA1 and RNAi-CsAGA2 plants. In cucurbitaceous plants, the non-sweet motif within the promoter of ClAGA2 is widely distributed in the promoter of its homologous genes. Taken together, we found RFOs hydrolysis occurred in the vascular tissues of fruits. CsAGA1 and CsAGA2 played key but partly distinct roles in the hydrolysis of RFOs. [ABSTRACT FROM AUTHOR]

• Comparing Hubbard. • AG owns larger leaf area, higher net photosynthetic rate and leaf stachyose level. • AG has larger phloem cross area and higher sugar concentration in phloem sap. • AG unloads stachyose directly into fruit without catabolism at fast growing stage. Atlantic Giant (AG), the world largest pumpkin, was bred through continuously crosses and strict selections from the small fruit ancestor. To understand the change caused by the artificial cross and selection in the recent 100 years, differences of morphology, anatomy and physiology between two cultivars with distinct fruit size in Cucurbita maxima , AG and Hubbard were investigated. Comparing with Hubbard, AG owns more fruit cell number and larger fruit cell volume at harvest stage, accompanied by larger leaves, higher net photosynthetic rate, lower leaf total sugar concentration, higher leaf stachyose level, larger peduncle vascular cross area and higher phloem sap sugar concentration. Further theoretical calculation indicates that AG needs more leaves and longer translocation time per day to support its huge fruit growth. In addition, considerable glucose and stachyose were found in the phloem sap and sarcocarp of AG respectively, suggesting different loading and unloading mechanisms are involved in the giant pumpkin growth. These results provide useful cues for improving cultivation and breeding techniques of giant pumpkins. [ABSTRACT FROM AUTHOR]

• Alternative polyadenylation produces three transcript isoforms of the cucumber CsSTSs. • Three isoforms revealed different relative stabilities among different leaves. • CsSTS1 was the most stable isoform in the fruit-node leaf. • Fruit setting induced the CsSTS1 exclusive expression in the leaf at the same node. • APA is a delicate mechanism for CsSTS to regulate cucumber source-sink balance. Alternative polyadenylation (APA) is a pervasive mechanism for gene regulation in eukaryotes. Stachyose is the main assimilate translocated in the cucumber phloem. Stachyose synthase (CsSTS) catalyzes the last step of stachyose biosynthesis in cucumber leaves and plays a key role in the regulation of assimilate partitioning between source and sink. In this study, three CsSTS mRNAs with the same open reading frame and the 5'untranslated region (UTR), but differing in their 3'UTRs, named CsSTS1 (short), CsSTS2 (medium), and CsSTS3 (long), were identified. Southern blot and sequence analysis of the cucumber genome confirmed that these transcripts are regulated through APA from a single gene. No significant difference of in vitro translation efficiency was found among three mRNAs. However, the relative stabilities of three transcripts varied among different tissues and different leaf development stages of cucumber. CsSTS1 expression in cucumber calli was up-regulated by the raffinose (substrate of CsSTS) and down-regulated by stachyose (product of CsSTS), respectively. In cucumber plants, all three isoforms have considerable expression in non-fruit node leaves. However, in fruit-carrying node leaves, the expression of CsSTS2 and CsSTS3 was severely inhibited and only CsSTS1 was highly expressed, indicating fruit setting has a remarkable effect on the relative expression level of three transcripts. This "fruit setting" effect could be observed until at least 36 h after the fruit was removed from the node. Our results suggest that abundant expression of CsSTS1 is beneficial for stachyose loading in source leaves, and APA is a delicate mechanism for CsSTS to regulate cucumber source-sink balance. [ABSTRACT FROM AUTHOR]