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The rhizosphere microbiota emerges as a novel component that expands plant adaptation to its environment, and thus paves the way for future breeding approaches. Knowledge regarding the "functional core microbiota", which refers to the microbial taxa bearing essential functions for holobiont fitness, is required to move forward in this area. The aim of the present study was to compare the functional microbiota recruited by different plant genotypes in order to identify itscore and variable components. Seven genotypes of Medicago truncatula (DZA315-16, DZA315-26, DZA045-6, F83005-5, SA028064, Jemalong A17 and J6), representatives of a core collection of 184 genotypes, were studied. Functional genes have been described using shotgun metagenomics followed by Prodigal. Core and variable functional microbiota have been identified based on shared genes and on genes explaining differences among the genotypes, respectively.Functional assignments have been obtained based on proteins annotation and Gene Onthology using BlastX and EggNOG. 76,264 genes were shared, whilst 3547 genes explained the differences between the three DZA genotypes and SA, 4662 among the three DZA and the F, A17, J6 genotypes, and 32 among SA and the three genotypes F, A17, J6. 60.5% of these genes have been assigned to biological processes, 22.6% to cellular components and 16.9% to molecular functions.Particularly, inorganic ion, amino-acid, and carbohydrate transport were the most represented in biological processes. This global analysis shows that different genotypes modulate rhizosphere microbial functional genes and provides new insights into the variable and core microbiota among different plant genotypes

In a context of climate change, with more frequent drought events and heatwaves, it is predicted that soybean yields will drastically decrease in the near future. Soybean being the most widely grown legume crop in the world, there is an urgent need to improve its ability to sustain its growth under such conditions in order to guarantee high levels of productivity. The aim of this study was to explore the influence of heat and/or water stress on soybean growth and its water and mineral nutritions. Two soybean genotypes, displaying contrasted root architectures during their vegetative stage were grown under controlled conditions in the 4PMI high-throughput phenotyping platform where either optimal conditions, or heatwaves, or water stress, or both heatwaves and water stress were applied. Plants were characterized for their morphology, their water uptake and the mineral composition of their tissues. An ecophysiological structure-function framework, enabled us to link structural variables (leaf area, root architecture, biomass, etc.) to functional variables (water use efficiency, element uptake efficiencies…) in order to understand the interactions between water and element flows, and to quantify plant overall tolerance to each stress. Under combined stress conditions one genotype appeared to be more susceptible than the other genotype. No significant change in structural variable was observed in response to the double stress between the two genotypes. However, it appeared that the genotypic difference was more related to functional changes, especially with regard to water absorption. A complementary analysis of the plant ionome under the different stresses, highlighted plant strategies promoting soybean growth under these two stresses, and offered new perspectives for crop adaptation to climate change.

In this study, the effect of annealing atmosphere on the electrical properties, optical properties, microstructure and defects of ZnO∶Al films was investigated in detail. The crystallization, surface and fracture morphologies, electrical properties, resistivity, transmittance, Raman vibration and photoluminescence of ZnO∶Al films were characterized by SEM, XRD, Hall effect test instruments, ultraviolet-visible spectrophotometer, Raman spectra and PL spectra. The results show that after annealing in air atmosphere, the carrier concentration of AZO films decreases from 1.63 × 1020 cm−3 to 7.1 × 1018 cm−3, the optical band gap varies from 3.51 eV to 3.37 eV, the transmittance in NIR increased and the band edge emission in PL spectrum shifted from 3.49 eV to 3.34 eV. On the other hand, while the carrier concentration of AZO films annealing in H2 atmosphere was 5.3 × 1020 cm-3, the optical band gap increases to 3.78 eV, the transmittance in NIR decreases remarkably, the emission intensity of the band edge increases by more than 10 times and the band edge emission in PL spectrum shifts to 3.57 eV. Furthermore, the 4 order LO phonons are observed in ZnO:Al films annealed in air.

In a context of climate change, with more frequent drought events and heatwaves, it ispredicted that soybean yields will drastically decrease in the near future. Soybean being themost widely grown legume crop in the world, there is an urgent need to improve its ability tosustain its growth under such conditions in order to guarantee high levels of productivity. Theaim of this study was to explore the influence of heat and/or water stress on soybean growthand its water and mineral nutritions. Two soybean genotypes, displaying contrasted rootarchitectures during their vegetative stage were grown under controlled conditions in the4PMI high-throughput phenotyping platform where either optimal conditions, or heatwaves,or water stress, or both heatwaves and water stress were applied. Plants were characterized fortheir morphology, their water uptake, the mineral composition of their tissues and the roottranscriptome. An ecophysiological structure-function framework, enabled us to linkstructural variables (leaf area, root architecture, biomass, etc.) to functional variables (wateruse efficiency, element uptake efficiencies…) in order to understand the interactions betweenwater and element fluxes, and to quantify the overall tolerance of plants to each stress. Undercombined stress conditions, one genotype appeared more sensitive than the other. Nosignificant changes in structural variables were observed in response to the dual stressbetween the two genotypes. However, the genotypic difference was found to be more relatedto functional changes, particularly for water uptake. A complementary analysis of the plantionome and transcriptome under different stresses revealed plant strategies favoring soybeangrowth under these two stresses, and offered new perspectives for crop adaptation to climatechange.

Plants host in their rhizosphere a remarkable diversity of microorganisms that in return can promote plant growth and health. The microbiota that is systematically associated with a given plant genotype is called the core microbiota. However, the core microbiota has been mostly defined on taxonomic basis, whilst the microbiota recruited by the plant in different environments seems to share greater functional similarity and the concept of core functional microbiota has been proposed accordingly. The purpose of the PhD thesis is to give evidence of the existence of a core functional microbiota. The PhD thesis aims to: (i) assess the impact of different plant genotypes on the rhizosphere functional community through shotgun metagenomics; (ii) compare the genomics of different strains harboring functional genes identified at point (i) isolated from different soils; (iii) assess if these functional communities are beneficial for plant growth and nutrition through the building of Synthetic Communities (SCs); (iv) evaluate how the plant select these microbiota functions in different soils.In order to valuate if different genotypes belonging to a same plant species are able to select a functional core microbiota, the impact of seven Medicago truncatula genotypes on the rhizosphere microbiota was explored during the first year of my PhD thesis. The first results will be presented.

In this paper, the symmetric positive semidefinite Procrustes problem is considered. By using matrix inner product and matrix decomposition theory, an explicit expression of the solution is given. Based on the explicit expression given in this paper, it is easy to derive the explicit expression of the solution given by Woodgate [K.G. Woodgate. Least-squares solution of F = PG over positive semidefinite symmetric P . Linear Algebra Appl., 245:171–190, 1996.] and by Liao [A.P. Liao. On the least squares problem of a matrix equation. J. Comput. Math., 17:589–594, 1999.] for the Procrustes problem in some special cases. The explicit expression given in this paper also shows that the solution of the special inverse eigenvalue problem considered by Zhang [L. Zhang. A class of inverse eigenvalue problem for symmetric nonnegative definite matrices. J. Hunan Educational Inst., 2:11–17, 1995 (in Chinese).] can be computed exactly. Examples to illustrate the correctness of the theory results are given.

Plants deploy different strategies to respond and adapt to various stresses. Given that stresses affect plant growth and activity, the responses and tolerance of crops to stresses must be improved through genetic engineering. Inducible promoters, which have vital roles in gene expression and function, are highly desired in biotechnology applications. Thus, novel inducible promoters must be isolated and identified for genetic engineering to improve crop stress responses and tolerance. OsRhoGAPs are involved in plant defense against diverse stresses. In this study, we identified OsRhoGAP2, which is preferentially expressed in rice inflorescences. We isolated the OsRhoGAP2 promoter and analyzed its functions in transgenic Arabidopsis. We fused the GUS reporter with six 5′ deletion fragments (gp1–gp6) of the OsRhoGAP2 promoter with different lengths. Through histochemical analysis, we detected GUS activity in the inflorescences of transgenic Arabidopsis containing gp1, gp3, gp4, and gp5 constructs but not in transgenic Arabidopsis containing gp2 and gp6 constructs. The GUS activity in transgenic plants containing gp1–gp6 constructs changed under different stress treatments. Bioinformatics analysis and experimental results revealed that the core fragment involved in the inflorescence-preferential expression of OsRhoGAP2 and stress responses may be located in the − 706 bp to + 1 bp, or the translated start site, of OsRhoGAP2. Results indicate that OsRhoGAP2 has a conserved role in stress tolerance and exhibits tissue-specific expression patterns in several plant species. This work provides novel insights into the appropriate promoter resources for plant genetic transformation and useful references for biotechnologists to improve stress tolerance in rice.

n this paper, an iterative method to solve one kind of nonlinear matrix equation is discussed. For each initial matrix with some conditions, the matrix sequences generated by the iterative method are shown to lie in a fixed open ball. The matrix sequences generated by the iterative method are shown to converge to the only solution of the nonlinear matrix equation in the fixed closed ball. In addition, the error estimate of the approximate solution in the fixed closed ball, and a numerical example to illustrate the convergence results are given.

Soil salinization due to seawater intrusion along coastal areas is an increasing threat to rice cultivation worldwide. While the detrimental impact on rice growth and yield has been thoroughly studied, little is known about how severe salinity affects structure and function of paddy soil microbial communities. Here, we examined their short-term responses to half- and full-strength seawater salinity in controlled laboratory experiments. Slurry microcosms were incubated under anoxic conditions, with rice straw added as carbon source. Stress exposure time was for 2 days after a pre-incubation period of 7 days. Relative to the control, moderate (300 mM NaCl) and high (600 mM NaCl) salt stress suppressed both net consumption of acetate and methane production by 50% and 70%, respectively. Correspondingly, community-wide mRNA expression decreased by 50–65%, with significant changes in relative transcript abundance of family-level groups. mRNA turnover was clearly more responsive to salt stress than rRNA dynamics. Among bacteria, Clostridiaceae were most abundant and the only group whose transcriptional activity was strongly stimulated at 600 mM NaCl. In particular, clostridial mRNA involved in transcription/translation, fermentation, uptake and biosynthesis of compatible solutes, and flagellar motility was significantly enriched in response salt stress. None of the other bacterial groups were able to compete at 600 mM NaCl. Their responses to 300 mM NaCl were more diverse. Lachnospiraceae increased, Ruminococcaceae maintained, and Peptococcaceae, Veillonellaceae, and Syntrophomonadaceae decreased in relative mRNA abundance. Among methanogens, Methanosarcinaceae were most dominant. Relative to other family-level groups, salt stress induced a significant enrichment of transcripts related to the CO dehydrogenase/acetyl-coenzyme A synthase complex, methanogenesis, heat shock, ammonium uptake, and thermosomes, but the absolute abundance of methanosarcinal mRNA decreased. Most strikingly, the transcriptional activity of the Methanocellaceae was completely suppressed already at 300 mM NaCl. Apparently, the key taxonomic groups involved in the methanogenic breakdown of plant polymers significantly differ in their ability to cope with severe salt stress. Presumably, this different ability is directly linked to differences in their genetic potential and metabolic flexibility to reassign available energy resources for cellular adaptation to salt stress.

e18003 Background: Medical advance in the recent decades has turned cancer into a chronic disease. At the same time, quality of life (LoF) during the treatment period has emerged as a new concern of cancer patients. Rehabilitation therapy, which can help patients conquer fear and be more engaged in the process, has gradually attracted more attentions in China. We designed a survey, for both the cancer patients and their families, to understand their view of the rehabilitation therapy. Methods: We sent paper-based surveys to volunteers consisted of cancer patients and their families. Majority of patients are from 10 cancer centers at the southwest region of China. The main cancer types are lung cancer, breast cancer and colon cancer. The survey questions focus on: patients and their families’ engagement of the treatment, their view on rehabilitation therapy, and their method preference for the rehabilitation therapy. Results: We sent 2,000 copies of the survey and received 1,920 valid inputs. Below are the key findings. 1. Their biggest concern: the outcome of the treatment 55.8%, side effects 19.7%, financial burden 12.8% and mental stress 11.5%. 2. The importance of the rehabilitation therapy as compared to traditional medical treatment, such as surgery and chemotherapy: equally important 67.8%, less important 17.7%, more important 10.1%, no preference 4.4%. 3. The necessity of rehabilitation therapy: very necessary 65.7%, somewhat necessary 22.7%, not necessary 11.6%. 4. The first three reasons for participating rehabilitation therapy: it helped go through the treatment 42.8%, it improved quality of life 31.6% and it helped release their mental stress 22.3%. 5. The best form to conduct rehabilitation therapy: face-to-face communicate with the doctors 60.6%, telecommunication 15.8% and combination of both 22.1%. Conclusions: The results of the survey strongly indicate the demands for rehabilitation therapy. Patients started to understand it – more than half of them think it is as important as the traditional medical treatment. Patients’ quality of life and mental health, which is part of the holistic treatment, are gradually recognized. Next, we plan to group our survey results by types of cancers, patients and their families’ genders and age, as well as the local economics, to better understand the data. We hope this study can serve as a data point to help build China’s rehabilitation therapy infrastructure.

Iron is the fourth most abundant element in the Earth's crust.Microbially mediated dissimilatory Fe(Ⅲ) reduction is the major process for Fe(Ⅲ) reduction in anoxic environment.This review introduces the classification and the diversity of dissimilatory Fe(Ⅲ)-reducing microorganisms.There are two major groups of Fe(Ⅲ)-reducing microorganisms:one is microorganisms which could conserve energy to support growth from Fe(Ⅲ) reduction,and the other is those which could not conserve energy to support growth from Fe(Ⅲ) reduction.Dissimilatory Fe(Ⅲ)-reducing microorganisms are interspersed throughout Bacteria,Archaea and Fungi and have physiological diversity.Geobacter and Shewanella are the two most well studied genera among all the Fe(Ⅲ)-reducing microorganisms.This also summarizes the strategies that dissimilatory Fe(Ⅲ)-reducing bacteria use to transfer electron to extracellular Fe(Ⅲ) oxide minerals as well as the energy-generating central metabolism models of dissimilatory Fe(Ⅲ)-reducing bacteria.Direct contact,cellular appendage production,electron shuttling and chelation are the four potential strategies for the respiration of dissimilatory Fe(Ⅲ)-reducing bacteria.In Geobacter,acetate and other electron donors are completely oxidized via the tricarboxylic acid(TCA) cycle,generating ATP primarily from oxidative phosphorylation,while substrate-level phosphorylation is the primary source of energy conservation during anaerobic respiration of Shewanella.In addition,the environmental significances of dissimilatory Fe(Ⅲ)-reducing microorganisms are reviewed.Fe(Ⅲ)-reducing microorganisms might be one of the first,if not the first,of microbes involved in microbial respiration in the archaean biosphere,which contributes to the decomposition of organic matter in modern sedimentary environments and inhibition of methane production,exerts a broad range of impacts on the behavior of trace elements and have great potential in the bioremediation and microbial fuel cells.Finally,perspectives in the molecular ecology of dissimilatory Fe(Ⅲ)-reducing bacteria studies are proposed,e.g.the community structure of dissimilatory Fe(Ⅲ)-reducing bacteria in paddy soils,the contribution of dissimilatory Fe(Ⅲ)-reducing bacteria in the C-Fe-N coupling and the mechanism of dissimilatory Fe(Ⅲ)-reducing bacteria in the bioremediation with electrode and solar energy.

As switched reluctance machines (SRM) generally offer a simple and robust design, they are very suitable for an aircraft main engine fuel pump drive which needs to be actuated by fault-tolerant drives. In this paper two different fault-tolerant SRM topologies for fuel pump drive in aircraft are analytical compared: Firstly a 6/4-topology with two identical motors on one axis as a dual-redundancy drive system, and secondly a dual-channel 12/8-topology, where one 3-phase-system uses every other stator tooth and the second 3-phase-system that provides redundancies uses the rest of the stator teeth. The first of two schemes is turned out to be the better solution concerning ruggedness, weight, inertia, torque quality and magnetic isolation.

With the development of a low-carbon economy, the concept of low-carbon tourism is also increasingly popular. The implementation of low-carbon tourism responds to society's collective call for energy conservation and emission reduction. This is also the inevitable choice for sustainable development of tourism. This paper begins by explaining the concepts of low-carbon economy and low-carbon tourism; summarizes the content of low-carbon tourist attractions; describes the current plight of construction of low-carbon tourist attractions in China; and proposes some countermeasures for the construction of standard low-carbon tourist attractions.