Computation Rate Maximization in Multi-User Cooperation-Assisted Wireless-Powered Mobile Edge Computing with OFDMA

In the era of Internet of Things(Io T),mobile edge computing(MEC)and wireless power transfer(WPT)provide a prominent solution for computation-intensive applications to enhance computation capability and achieve sustainable energy supply.A wireless-powered mobile edge computing(WPMEC)system consisting of a hybrid access point(HAP)combined with MEC servers and many users is considered in this paper.In particular,a novel multiuser cooperation scheme based on orthogonal frequency division multiple access(OFDMA)is provided to improve the computation performance,where users can split the computation tasks into various parts for local computing,offloading to corresponding helper,and HAP for remote execution respectively with the aid of helper.Specifically,we aim at maximizing the weighted sum computation rate(WSCR)by optimizing time assignment,computation-task allocation,and transmission power at the same time while keeping energy neutrality in mind.We transform the original non-convex optimization problem to a convex optimization problem and then obtain a semi-closed form expression of the optimal solution by considering the convex optimization techniques.Simulation results demonstrate that the proposed multi-user cooperationassisted WPMEC scheme greatly improves the WSCR of all users than the existing schemes.In addition,OFDMA protocol increases the fairness and decreases delay among the users when compared to TDMA protocol.

Research on the Necessity of Building National-level Grape and Cherry Germplasm Resources Bank in Shandong Province

At present,the grape and cherry industries in Shandong are in the leading position in China and have driven the development of related high-end manufacturing industries such as wine,brandy,preserved fruit processing,fruit juice processing and health products. Therefore,vigorously developing the grape and cherry industries in Shandong Province and carrying out development and innovation are important parts of Shandong Province in responding to the strategy of national new and old kinetic energy conversion. However,currently the germplasm resources preserved in the fruit tree resources banks in China are only 45% of those in the US and 27. 2% of those in the EU. Moreover,the development of fruit trees resources banks in Shandong is relatively backward in China,and there is still no banks related with grape and cherry germplasm resources in Shandong. Therefore,importance can be attached to the agriculture,forestry,and animal husbandry to build germplasm resources banks for grape and cherry industries in Shandong Province. Building the national-level grape and cherry germplasm resources bank in Shandong Province can also promote the utilization of wild and farm germplasm resources in the future; advance the research on the genes related to disease resistance,stress resistance and quality of grapes and cherries; push forward the construction and development of cherry and grape mutants banks. It is conducive to the research on the agronomic traits of grapes and cherries,and can provide the parents resources for planting innovation and improving the quality of grapes and cherries,as well as promote the development and application of molecular markers of grapes and cherries,including the identification of lines and crossbreeding. Thereby,it cannot only promote the industry development,but also achieve the development of cultivation,breeding and basic research in an all-round way and the development of ＂ production,study and research＂ going side by side.

Identification of Differentially Expressed Genes in Grape Skin at Veraison and Maturity and Construction of Co-expression Network

The ripening process of grape is an important stage during grape growth and development. During this process, color of grape skin is the most obvious change. The molecular mechanism for the ripening of grape(a non-climacteric fruit, which ripens without ethylene and respiration bursts) is still unclear. Although numerous studies have been done on the changes in the contents of metabolites during grape ripening, the differentially expressed genes at veraison and maturity stages have not been systematically analyzed. In this study, 1 524 genes that are significantly differentially expressed in grape(Pinot Noir) skin at veraison and maturity stages were identified, and a co-expression network of these genes was built. Some of the eight co-expression modules we identified may be closely related to the synthesis or metabolism of anthocyanins, sugar acids, and other flavor substances. The transcription factor families WRKY, b ZIP, HSF and WOX may play an important role in the regulation of anthocyanin synthesis or metabolism. The results provide a foundation for further study of the molecular mechanism of grape ripening.

Advances in the Role of DNA Methylation and miRNAs in Plant Defense

DNA methylation and miRNAs are two important epigenetic molecular mechmxisms in plants. RNA-directed DNA methylation （RdDM） pathway is con- sidered as the most important mechanism of DNA methylation. A microRNA （miRNA） is processed from a 70-90-nucleotide-long single-stranded RNA precursor that forms a hairpin structure by Dicer enzyme, which plays an important role in plant development, regulation of plant gene expression and silencing of trans- posons. In recent years, a large number of studies have confirmed that DNA methylation and miRNAs play an important role in disease resistance mechanisms of plants. In this paper, recent progress on the role of DNA methylation and miRNAs in plant defense was summarized, which provided reference for revealing the re- lationship between disease resistance factors and epigenctic mechanisms in plants.

GmYSL7 controls iron uptake,allocation,and cellular response of nodules in soybean

Iron(Fe)is essential for DNA synthesis,photosynthesis and respiration of plants.The demand for Fe substantially increases during legumesrhizobia symbiotic nitrogen fixation because of the synthesis of leghemoglobin in the host and Fecontaining proteins in bacteroids.However,the mechanism by which plant controls iron transport to nodules remains largely unknown.Here we demonstrate that GmYSL7 serves as a key regulator controlling Fe uptake from root to nodule and distribution in soybean nodules.GmYSL7 is Fe responsive and GmYSL7 transports iron across the membrane and into the infected cells of nodules.Alterations of GmYSL7 substantially affect iron distribution between root and nodule,resulting in defective growth of nodules and reduced nitrogenase activity.GmYSL7 knockout increases the expression of GmbHLH300,a transcription factor required for Fe response of nodules.Overexpression of GmbHLH300 decreases nodule number,nitrogenase activity and Fe content in nodules.Remarkably,GmbHLH300 directly binds to the promoters of ENOD93 and GmLbs,which regulate nodule number and nitrogenase activity,and represses their transcription.Our data reveal a new role of GmYSL7 in controlling Fe transport from host root to nodule and Fe distribution in nodule cells,and uncover a molecular mechanism by which Fe affects nodule number and nitrogenase activity.

A NIR ratiometric fluorescent biosensor for sensitive detection and imaging of α-L-fucosidase in living cells and HCC tumor-bearing mice

Detection and imaging of α-L-fucosidase(AFU)is of great value to understand its roles in hepatocellular carcinoma(HCC)and tumor early diagnosis,but ideal assays are still lacking.Herein,a near-infrared(NIR)fluorescent biosensor(α-Fuc-DCM)was elaborately designed and synthesized for rapid and ratiometric detection of AFU activity in cells and HCC tumor mouse models.In the presence of AFU,this biosensor shows an enhancement in NIR emission in a ratiometric manner,which significantly improves the detection accuracy with the limit of detection as low as 4.8 mU/mL.Taking advantage of these merits,the activity of AFU in lysosomes could be visualized using ratiometric and NIR dual modality in living cells.Furthermore,its remarkable application for monitoring of endogenous AFU activity in HCC tumor-bearing mouse model is also demonstrated with bright fluorescence signal,which indicated that the biosensor could clearly monitor the liver tumor in the early stage.Importantly,the α-Fuc-DCM probe can be utilized to detect the AFU in serum from HCC patients.This strategy offers a promising biosensor system for early diagnosis of HCC and studying the roles of AFU in cancers.

Counteraction of ABA-Mediated Inhibition of Seed Germination and Seedling Establishment by ABA Signaling Terminator in Arabidopsis

Seed germination and seedling establishment are important for the reproductive success of plants,but seeds and seedlings typically encounter constantly changing environmental conditions.By inhibiting seed germination and post-germinative growth through the PYR1/PYL/RCAR ABA receptors and PP2C co-receptors,the phytohormone abscisic acid(ABA)prevents premature germination and seedling growth under unfavorable conditions.However,little is known about how the ABA-mediated inhibition of seed germination and seedling establishment is thwarted.Here,we report that ABA Signaling Terminator(ABT),a WD40 protein,efficiently switches off ABA signaling and is critical for seed germination and seedling establishment.ABT is induced by ABA in a PYR1/PYL/RCAR-PP2C-dependent manner.Overexpression of ABT promotes seed germination and seedling greening in the presence of ABA,whereas knockout of ABT has the opposite effect.We found that ABT interacts with the PYR1/PYL/RCAR and PP2C proteins,interferes with the interaction between PYR1/PYL4 and ABI1/ABI2,and hampers the inhibition of ABI1/ABI2 by ABA-bound PYR1/PYL4,thereby terminating ABA signaling.Taken together,our results reveal a core mechanism of ABA signaling termination that is critical for seed germination and seedling establishment in Arabidopsis.

Regional and Global Land Data Assimilation Systems: Innovations,Challenges, and Prospects

Since the North American and Global Land Data Assimilation Systems(NLDAS and GLDAS) were established in2004, significant progress has been made in development of regional and global LDASs. National, regional, projectbased, and global LDASs are widely developed across the world. This paper summarizes and overviews the development, current status, applications, challenges, and future prospects of these LDASs. We first introduce various regional and global LDASs including their development history and innovations, and then discuss the evaluation, validation, and applications(from numerical model prediction to water resources management) of these LDASs. More importantly, we document in detail some specific challenges that the LDASs are facing: quality of the in-situ observations, satellite retrievals, reanalysis data, surface meteorological forcing data, and soil and vegetation databases; land surface model physical process treatment and parameter calibration; land data assimilation difficulties; and spatial scale incompatibility problems. Finally, some prospects such as the use of land information system software, the unified global LDAS system with nesting concept and hyper-resolution, and uncertainty estimates for model structure,parameters, and forcing are discussed.