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Shortage of fresh water resources has become a fundamental and chronic problem for sustainable agriculture development in arid regions. Use of saline water irrigation has become an important means for alleviating fresh water scarcity. However, long-term irrigation with saline water may cause salt accumulation in the soil, and further affect nitrogen transformation and N 2 O emission. For this, we conducted a 10-year field experiment to evaluate the effect of irrigation water salinity and N amount on N 2 O emission and denitrifier bacteria communities. The experimental design was a 2 × 2 factorial with two irrigation water salinity levels (0.35 and 8.04 dS m−1, representing SF and SH) and two N amounts (0 and 360 kg N ha−1, representing N0 and N360). The results indicated that long-term saline water irrigation significantly increased soil salinity, moisture, and NH 4 -N content, while decreased soil pH, NO 3 -N, organic matter, and total nitrogen. Irrigation with saline water significantly inhibited N 2 O emission, that was associated with a level decreased by 45.19% (N0) and 43.50% (N360) compared with irrigation with fresh water. N 2 O emission increased as the N amount increased, the N 2 O emission was 161% higher in the N360 treatment than in the N0 treatment. In the unfertilized plots, saline water irrigation significantly reduced the activity of denitrifying enzymes, the abundance of nirK, nirS, and nosZ, as well as the diversity of denitrifying bacteria communities. In the fertilized plots, saline water irrigation did not significantly affect the abundance of nosZ, while significantly reduced the abundance of nirK and nirS. Saline water irrigation and nitrogen application altered the community structures of denitrifying bacteria with nirK, nirS, and nosZ, irrigation water salinity seemed to be having a greater impact on denitrifying bacteria community in comparison with fertilization. LEfSe analysis demonstrated denitrifying bacterial potential biomarkers increased as the water salinity increased, meaning that saline water irrigation could alter community structures of denitrifying bacteria, and promote the growth of dominant species. Our findings indicate that increased abundance of nosZ, nirK, and nirS would promote N 2 O emission, and although long-term saline water reduced soil N 2 O emission, it resulted in continuous increase of soil salinity. • Saline water irrigation reduced the abundance of nirK, nirS, and nosZ in the unfertilized plots. • Saline water reduced the abundance of nirK and nirS in the fertilized plots. • Denitrifying bacterial potential biomarkers increased as the water salinity increased. • NirS bacteria may be a dominant microflora in the process of denitrification. • Saline water irrigation inhibited N 2 O emission and denitrifying enzyme activities in soil. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid attitude control scheme of L1 adaptive and dynamic inversion for unmanned aerial vehicle with actuator faults, where both gain fault and bias fault are considered. Firstly, dynamic inversion is employed to track attitude angles in the outer loop and ensures the rapid response. Secondly, an L1 adaptive controller for the inner loop is established to compensate for system uncertainty and uncertainty caused by actuator failures. Thirdly, the analysis of steady-state and transient performance is given by Lyapunov theory. Finally, simulation results prove the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The advancement of mobile Internet and ubiquitous computing is facilitating various crowdsourcing services in which individuals or organizations obtain goods and services with less time and monetary cost. Recently, crowdphotographing, an emerging self-service mode over the mobile Internet, is to recruit several users to take the pictures via incentive mechanism. Mobile users can earn the money by executing their requested sensing tasks. Thus, how to make an efficient pricing strategy is becoming a challenge issue in crowdphotographing. To this end, this paper mainly investigates the rationality and optimization of task pricing for crowdphotographing. First, we analyze the correlation among tasks pricing, location of members, and tasks. Then, a multivariable linear regression model is adopted for determining the task pricing strategy. Further, an improved pricing model is devised by considering the package of several tasks that can be packaged in terms of their locations distribution. [ABSTRACT FROM AUTHOR]

Compressed Sensing (CS), as a promising paradigm for acquiring signals, is playing an increasing important role in many real-world applications. One of the major components of CS is sparse signal recovery in which greedy algorithm is well-known for its speed and performance. Unfortunately, in many classic greedy algorithms, such as OMP and CoSaMP, the real sparsity is a key prior information, but it is blind. In another words, the true sparsity is not available for many practical applications. Due to this disadvantage, the performance of these algorithms are significantly reduced. In order to avoid too much dependence of classic greedy algorithms on the true sparsity, this paper proposed an efficient reconstruction greedy algorithm for practical Compressed Sensing, termed stepwise optimal sparsity pursuit (SOSP). Differs from the existing algorithms, the unique feature of SOSP algorithm is that the assumption of sparsity is needed instead of the true sparsity. Hence, the limitations of sparsity in practical application can be tackled. Based on an arbitrary initial sparsity satisfying certain conditions, the SOSP algorithm employs two variable step sizes to hunt for the optimal sparsity step by step by comparing the final reconstruction residues. Since the proposed SOSP algorithm preserves the ideas of original algorithms and innovates the prior information of sparsity, thus it is applicable to any effective algorithm requiring known sparsity. Extensive experiments are conducted in order to demonstrate that the SOSP algorithm offers a superior reconstruction performance in terms of discarding the true sparsity. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Nitrogen fertilization affects plants directly and herbivorous insects indirectly. Although insect species and even genotypes are known to differ in their responses to nitrogen fertilization, the physiological and molecular mechanisms remain unclear. This study assessed the fecundity and related regulatory signaling pathways in the green and red morphs of pea aphid (Acyrthosiphon pisum) feeding on Medicago truncatula with and without nitrogen fertilization. RESULTS: Nitrogen fertilization significantly increased foliar amino acid concentrations and consequently increased the concentrations of several individual essential amino acids in body tissue of the green morph. The increased concentration of Leu, Ile, Met and Val was consistent with enhanced biosynthesis of these amino acids in the endosymbiont Buchnera. Under nitrogen fertilization, Leu and Met accumulated in the green morph enhanced the target of rapamycin (TOR) signaling pathway, which consequently increased fecundity by promoting vitellogenin synthesis. In the red morph, however, nitrogen fertilization did not change the concentration of essential amino acids, TOR signaling or fecundity. CONCLUSION: Specific amino acids accumulation and the nutrient transduction pathway in pea aphids are responsible for genotype‐specific fecundity in response to nitrogen fertilization, which could be used as potential target for pest control. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

When larvae of rootworms feed on maize roots they induce the emission of the sesquiterpene (E)-β-caryophyllene (EβC). EβC is attractive to entomopathogenic nematodes, which parasitize and rapidly kill the larvae, thereby protecting the roots from further damage. Certain root-colonizing bacteria of the genus Pseudomonas also benefit plants by promoting growth, suppressing pathogens or inducing systemic resistance (ISR), and some strains also have insecticidal activity. It remains unknown how these bacteria influence the emissions of root volatiles. In this study, we evaluated how colonization by the growth-promoting and insecticidal bacteria Pseudomonas protegens CHA0 and Pseudomonas chlororaphis PCL1391 affects the production of EβC upon feeding by larvae of the banded cucumber beetle, Diabrotica balteata Le Conte (Coleoptera: Chrysomelidae). Using chemical analysis and gene expression measurements, we found that EβC production and the expression of the EβC synthase gene (tps23) were enhanced in Pseudomonas protegens CHA0-colonized roots after 72 h of D. balteata feeding. Undamaged roots colonized by Pseudomonas spp. showed no measurable increase in EβC production, but a slight increase in tps23 expression. Pseudomonas colonization did not affect root biomass, but larvae that fed on roots colonized by P. protegens CHA0 tended to gain more weight than larvae that fed on roots colonized by P. chlororaphis PCL1391. Larvae mortality on Pseudomonas spp. colonized roots was slightly, but not significantly higher than on non-colonized control roots. The observed enhanced production of EβC upon Pseudomonas protegens CHA0 colonization may enhance the roots’ attractiveness to entomopathogenic nematodes, but this remains to be tested. [ABSTRACT FROM AUTHOR]

Summary: Resistance against pathogens and herbivorous insects in many plant results from the expression of resistance (R) genes. Few reports, however, have considered the effects of elevated CO2 on R gene‐based resistance in plants. The current study determined the responses of two near isogenic Medicago truncatula genotypes (Jester has an R gene and A17 does not) to the pea aphid and elevated CO2 in open‐top chambers in the field. Aphid abundance, mean relative growth rate and feeding efficiency were increased by elevated CO2 on A17 plants but were reduced on Jester plants. According to proteomic and gene expression data, elevated CO2 enhanced pathogen‐associated molecular pattern (PAMP)‐triggered immunity (PTI) but decreased the effector‐triggered immunity (ETI) in aphid‐infested A17 plants. For aphid‐infested Jester plants, by contrast, elevated CO2 enhanced the ETI‐related heat shock protein (HSP) 90 and its co‐chaperones, the jasmonic acid (JA) signaling pathway, and ubiquitin‐mediated proteolysis. In a loss‐of‐function experiment, silencing of the HSP90 gene in Jester plants impaired the JA signaling pathway and ubiquitin‐mediated proteolysis against the aphid under ambient CO2, and negated the increased resistance against the aphid under elevated CO2. Our results suggest that increases in expression of HSP90 are responsible for the enhanced resistance against the aphid under elevated CO2. [ABSTRACT FROM AUTHOR]

A novel strategy for improving the immobilization of heavy metals during the use of electroplating sludge in the production of clay bricks, was proposed by the addition of waste glass. Waste glass addition reduced open porosity and surface area, and enhanced compressive strength remarkably. With the adding amount of waste glass powder up to 30 wt.%, surface area and open porosity declined from 0.84 to 0.05 m 2 /g and from 10.69 to 1.16%, respectively. Compressive strength increased from 20 to 32.7 MPa. Moreover, the leaching concentration of heavy metals decreased considerably and met the regulation standard. Heavy metals, Cu and Zn, have been incorporated into stable spinels phase and adding waste glass was favored to the formation of spinel. It was regarded that waste glass and andesine melted and formed liquid phase during firing process, which improved the mass transfer and the reaction kinetic of spinels formation. The liquid phase filled in the pores and densified bricks body, which also play a important role in preventing heavy metals from releasing. Overall results suggested the addition of waste glass powder was a promising method in improving immobilization of heavy metals during the use of electroplating sludge in production of clay bricks. [ABSTRACT FROM AUTHOR]

The role of selenium in proteins and nucleic acids is well-established, but the pathway for incorporating selenium into small molecules remains unknown. Now, using bioinformatics tools, a selenium-incorporating gene cluster is discovered from immense genomic data, leading to the identification of selenoneine from microorganisms and the elucidation of a selenium incorporation pathway. [ABSTRACT FROM AUTHOR]

The Aux/ IAA ( IAA) gene family, involved in the auxin signalling pathway, acts as an important regulator in plant growth and development. In this study, we explored the evolutionary trajectory of the IAA family in common wheat. The results showed ten pairs of paralogs among 34 TaIAA family members. Seven of the pairs might have undergone segmental duplication, and the other three pairs appear to have experienced tandem duplication. Except for TaIAA15-16, these duplication events occurred in the ancestral genomes before the divergence of Triticeae. After that point, two polyploidization events shaped the current TaIAA family consisting of three subgenomic copies. The structure or expression pattern of the TaIAA family begins to differentiate in the hexaploid genome, where TaIAAs in the D genome lost more genes (eight) and protein secondary structures (α1, α3 and β5) than did the other two genomes. Expression analysis showed that six members of the TaIAA family were not expressed, and members such as TaIAA8, 15, 16, 28 and 33 exhibited tissue-specific expression patterns. In addition, three of the ten pairs of paralogs ( TaIAA5- 12, TaIAA15- 16 and TaIAA29- 30) showed similar expression patterns, and another five paralog pairs displayed differential expression patterns. Phylogenetic analysis showed that paralog pairs with high rates of evolution ( ω > ω ), particularly TaIAA15- 16 and TaIAA29- 30, experienced greater motif loss, with only zero to two interacting IAA proteins. In contrast, most paralogous genes with low ω, such as TaIAA5-12, had more complete motifs and higher degrees of interaction with other family members. [ABSTRACT FROM AUTHOR]