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For the multi-label classification task of remote sensing images (RSIs), it is difficult to accurately extract feature information from complex land covers, and it is easy to generate redundant features by ordinary convolution extraction features. This paper proposes a multi-label classification model for multi-source RSIs that combines dense convolution and an attention mechanism. This method adds fusion channel attention and a spatial attention mechanism to each dense block module of the DenseNet, and the sigmoid activation function replaces the softmax activation function in multi-label classification. The improved model retains the main features of RSIs to the greatest extent and enhances the feature extraction of the images. The model can integrate local features, capture global dependencies, and aggregate contextual information to improve the multi-label land cover classification accuracy of RSIs. We conducted comparative experiments on the SEN12-MS and UC-Merced land cover dataset and analyzed the evaluation indicators. The experimental results show that this method effectively improves the multi-label classification accuracy of RSIs. [ABSTRACT FROM AUTHOR]

Aiming at the problems of data loss and uneven energy consumption in wireless sensor networks during data transmission, this paper proposes a ReInForM transmission fault-tolerant routing algorithm based on energy selection and erasure code fault-tolerant machines (E-ReInForMIF). The E-ReInForMIF algorithm improves the multi-path routing algorithm by combining an erasure coding fault-tolerant machine and node residual energy sorting selection. First, the erasure coding fault-tolerant machine is used to encode the signal, determine the number of transmission paths through multi-path routing, and then select the specific node of the next hop by sorting the residual energy of the node. The E-ReInForMIF routing algorithm effectively solves the problems of uneven energy consumption and data loss in data transmission, improving network lifespan and transmission reliability. Finally, the signal is decoded. The simulation results show that the E-ReInForMIF routing algorithm is superior to the ReInForM routing algorithm in improving the reliability of data transmission. [ABSTRACT FROM AUTHOR]

The leaf area index (LAI) is an important physiological parameter that characterizes the growth of crops. Traditional measurement could not meet the demands of large-scale accurate monitoring. QGA-ELM and LS-SVM algorithm combined with UAV remote sensing images was used to achieve the goal of building large-scale fast inversion modeling of LAI in this paper. Linear and nonlinear models were constructed for comparing the correlation between six spectral indices and LAI by categorizing the nitrogen level. The LS-SVM model was constructed to replace traditional linear model, the determination coefficient of correction set and prediction set (R2C and R2P) were 0.6496 and 0.6814; and the root mean square error of correction set and prediction set (RMSEC and RMSEP) were 0.5702 and 0.6842, respectively. The results showed that the inversion of edge objects in noncrop areas was not so stable. In order to address the problem, an improvement based on the extreme learning machine (ELM) and quantum genetic algorithm (QGA) with probabilistic evolution were used to combine with LS-SVM for overcoming the problem which the hidden layer connection weight and threshold randomly generated and solve the problems of slow regression of nonlinear data and insufficient model generalization ability. Compared with traditional linear and nonlinear regression, the QGA-ELM combined with LS-SVM showed the following: (1) improving the optimization ability greatly and avoid the prematurity of GA (genetic algorithm) effectively. The generalization performance has also been enhanced. (2) R2P of prediction set was 0.6686, and RMSEP was 0.8952 which could reflect the growth and distribution trend of rice in the regional scale. (3) Adapting different fertilization gradients (deficiency to excess) could provide basis for LAI inversion in different varieties and accumulated temperature zone of rice. The results above showed that QGA-ELM combined with LS-SVM could improve the stability of the model greatly and provide reference significance for rice growth inversion. [ABSTRACT FROM AUTHOR]

Cross-linked poly(vinylbenzyl chloride) (PVBC) microspheres tethered with polymer brushes containing quaternary ammonium ions were developed as an anionic adsorbent for the efficient removal of phenol from aqueous solutions. The terminal alkyl chlorine groups on the PVBC microspheres served as anchor sites for the grafting of poly(dimethylaminopropyl methacrylamide) (PDMAPMA) brushes via surface-initiated atom transfer radical polymerization (ATRP). The pendent tertiary amino groups of the PDMAPMA chains were converted into quaternary ammonium ions by N-alkylation reaction to produce anionic adsorption functionality. Success for each reaction step was ascertained by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Batch adsorption results demonstrated that solution pH values in a wide range of 3.0–11.0 had no evident effect on phenol adsorption by the quaternized PDMAPMA-grafted PVBC (i.e., PVBC-g-QPDMAPMA) microspheres, and that the adsorption capacity of the microspheres increased with the grafting density of the quaternized PDMAPMA brushes within 6 h. The so-synthesized anionic adsorbents had a rapid pseudo-first-order-adsorption kinetic (equilibrium achieved within 60 min), and the Langmuir model-fitted maximum adsorption capacity of phenol was approximately 2.23 mmol g−1 at pH 6.5 with an initial concentration of 1.05–5.31 mmol L−1 (i.e., 100–500 mg L−1). The calculated thermodynamic parameters revealed an exothermic and spontaneous adsorption process of phenol onto the quaternized QPDMAPMA-grafted microspheres. Desorption and adsorption cycle experiments demonstrated that the anionic adsorbents loaded with phenol were found to be readily regenerated in a 0.1 mol L−1 NaOH solution, and that the adsorption capacity decreased by less than 10% upon five cycles. [ABSTRACT FROM AUTHOR]

During germination, phytate, a major phosphate compound in seeds, is degraded into inorganic phosphorus (Pi) for differentiation of new tissues via catalysis. OsPHY1, a member of phytase genes in rice, has previously been found to show high expression levels in the endosperm and hypocotyl during germination and is involved in the degradation of seed phytate. In this study, we investigated the transcriptional mechanisms of OsPHY1 via OsPHY1 promoter- GUS analysis. The results of GUS histochemical staining and activities in tobaccos harboring OsPHY1- GUS reveal that the reporter gene is strongly expressed in the hypocotyl and responds to diverse stimuli cues initiated by phytohormones abscisic acid (ABA), gibberellin (GA 3), and indole-3-acetic acid (IAA), as well as osmotic stresses of salt, drought, and cold. The results indicate that the cis-regulatory element CANBNNAPA regulates gene hypocotyl-predominant expression. ABRE and GAREAT are involved in gene responses to ABA and GA 3, respectively, and DRECRTCOREAT is involved in gene responses to stresses of salt, drought, and cold. In addition, the responses of OsPHY1 and part-osmotic stress-responsive genes to salt, drought, and cold mediated by DRECRTCOREAT are largely accomplished through the ABA-dependent pathway with the involvement of the ABA responsive cis-regulatory element ABRE. Our results reveal that the degradation of seed phytate during germination mediated by OsPHY1 is regulated in a fine-tune manner with the involvement of diverse cis-regulatory elements at the transcription level. [ABSTRACT FROM AUTHOR]

Abstract: Salt stress is one of the major abiotic stresses affecting plant growth, development, and productivity. In this study, we functionally characterized a wheat vacuolar Na+/H+ antiporter gene (TaNHX3). TaNHX3 is 78.9% identical with TaNHX2 in nucleic acid level, encoding a polypeptide of 522 amino acids (aa). TaNHX3 is targeted onto tonoplast after ER sorting and can complement the growth under salt stress in a yeast mutant with a defective vacuolar Na+/H+ antiporter exchange. TaNHX3 transcripts were induced by applying salt stress in wheat cultivars. More TaNHX3 were detected in the salt-stress-resistant cultivar Ji 7369 compared with the salt-stress-sensitive cultivar Shimai 12 and Ji-Shi-3, an isogenic line derived from aforementioned cultivars with Shimai 12 genetic background. The ectopic TaNHX3 expression in tobacco significantly enhanced the plant tolerance to salt stress. Compared with control plants, the TaNHX3 overexpressing plants displayed no varied Na+ contents and accumulated more Na+ amount in plants. However, they exhibited higher fresh and dry weights, more accumulative nitrogen, phosphorus, and potassium, higher contents of chlorophyll, carotenoid, soluble protein, higher activities of the antioxidant enzymes including superoxide dismutase, catalase, and peroxidase, and lower malondialdehyde and H2O2 amount. Our results indicated that TaNHX3 plays an important role in regulating the cytosolic Na+ transportation within vacuoles under high salinity, alleviating the Na+ damage effects. The improved salt stress tolerance in TaNHX3 overexpressing tobacco plants is closely associated with the improvement of the aforementioned physiological processes. TaNHX3 can be used as a candidate gene for molecular breeding of salt-tolerant plants. [Copyright &y& Elsevier]

Salt stress is one of the major abiotic stresses affecting plant growth, development, and productivity. In this study, we functionally characterized a wheat vacuolar Na(+)/H(+) antiporter gene (TaNHX3). TaNHX3 is 78.9% identical with TaNHX2 in nucleic acid level, encoding a polypeptide of 522 amino acids (aa). TaNHX3 is targeted onto tonoplast after ER sorting and can complement the growth under salt stress in a yeast mutant with a defective vacuolar Na(+)/H(+) antiporter exchange. TaNHX3 transcripts were induced by applying salt stress in wheat cultivars. More TaNHX3 were detected in the salt-stress-resistant cultivar Ji 7369 compared with the salt-stress-sensitive cultivar Shimai 12 and Ji-Shi-3, an isogenic line derived from aforementioned cultivars with Shimai 12 genetic background. The ectopic TaNHX3 expression in tobacco significantly enhanced the plant tolerance to salt stress. Compared with control plants, the TaNHX3 overexpressing plants displayed no varied Na(+) contents and accumulated more Na(+) amount in plants. However, they exhibited higher fresh and dry weights, more accumulative nitrogen, phosphorus, and potassium, higher contents of chlorophyll, carotenoid, soluble protein, higher activities of the antioxidant enzymes including superoxide dismutase, catalase, and peroxidase, and lower malondialdehyde and H2O2 amount. Our results indicated that TaNHX3 plays an important role in regulating the cytosolic Na(+) transportation within vacuoles under high salinity, alleviating the Na(+) damage effects. The improved salt stress tolerance in TaNHX3 overexpressing tobacco plants is closely associated with the improvement of the aforementioned physiological processes. TaNHX3 can be used as a candidate gene for molecular breeding of salt-tolerant plants., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)