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Background The assembly of the rhizomicrobiome, i.e., the microbiome in the soil adhering to the root, is influenced by soil conditions. Here, we investigated the core rhizomicrobiome of a wild plant species transplanted to an identical soil type with small differences in chemical factors and the impact of these soil chemistry differences on the core microbiome after long-term cultivation. We sampled three natural reserve populations of wild rice (i.e., in situ) and three populations of transplanted in situ wild rice grown ex situ for more than 40 years to determine the core wild rice rhizomicrobiome. Results Generalized joint attribute modeling (GJAM) identified a total of 44 amplicon sequence variants (ASVs) composing the core wild rice rhizomicrobiome, including 35 bacterial ASVs belonging to the phyla Actinobacteria, Chloroflexi, Firmicutes, and Nitrospirae and 9 fungal ASVs belonging to the phyla Ascomycota, Basidiomycota, and Rozellomycota. Nine core bacterial ASVs belonging to the genera Haliangium, Anaeromyxobacter, Bradyrhizobium, and Bacillus were more abundant in the rhizosphere of ex situ wild rice than in the rhizosphere of in situ wild rice. The main ecological functions of the core microbiome were nitrogen fixation, manganese oxidation, aerobic chemoheterotrophy, chemoheterotrophy, and iron respiration, suggesting roles of the core rhizomicrobiome in improving nutrient resource acquisition for rice growth. The function of the core rhizosphere bacterial community was significantly (p < 0.05) shaped by electrical conductivity, total nitrogen, and available phosphorus present in the soil adhering to the roots. Conclusion We discovered that nitrogen, manganese, iron, and carbon resource acquisition are potential functions of the core rhizomicrobiome of the wild rice Oryza rufipogon. Our findings suggest that further potential utilization of the core rhizomicrobiome should consider the effects of soil properties on the abundances of different genera.

The rhizosphere-associated microbiome impacts plant performance and tolerance to abiotic and biotic stresses. Despite increasing recognition of the enormous functional role of the rhizomicrobiome on the survival of wild plant species growing under harsh environmental conditions, such as nutrient, water, temperature, and pathogen stresses, the utilization of the rhizosphere microbial community in domesticated rice production systems has been limited. Better insight into how this role of the rhizomicrobiome for the performance and survival of wild plants has been changed during domestication and development of present domesticated crops, may help to assess the potential of the rhizomicrobial community to improve the sustainable production of these crops. Here, we review the current knowledge of the effect of domestication on the microbial rhizosphere community of rice and other crops by comparing its diversity, structure, and function in wild versus domesticated species. We also examine the existing information on the impact of the plant on their physico-chemical environment. We propose that a holobiont approach should be explored in future studies by combining detailed analysis of the dynamics of the physicochemical microenvironment surrounding roots to systematically investigate the microenvironment–plant–rhizomicrobe interactions during rice domestication, and suggest focusing on the use of beneficial microbes (arbuscular mycorrhizal fungi and Nitrogen fixers), denitrifiers and methane consumers to improve the sustainable production of rice.

For workpieces with discontinuous surface characteristics such as shafts with keyways, obtaining continuous and valid measurement data is essential for assessing machining quality. In this paper, a Bayesian approach based on prior knowledge is proposed to evaluate the geometric characteristics of the discontinuous surface. Effective measurement data for discontinues surface is supplemented by accurate Bayesian parameter estimation. By using the supplemented data, the dimensional error and roundness error can be calculated. Using the in-process measurement method, the process progress can be adjusted in time according to the error value to realize the fusion control of dimension and roundness. Experimental investigations for machining multi-keyway shaft are carried out based on the proposed method. The results show that grinding workpieces with discontinuous surface by using the in-process measurement method based on Bayesian theory can significantly improve product quality and efficiency.

Additional file 4: Figure S2. The principal coordinate analysis (PCoA) of the (A) bacterial and (B) fungal communities in the rhizosphere of wild rice populations of the in situ natural reserves (ZTI, Zhangtang; AJSI, Anjiashan; STSI, Shuitaoshu) and ex situ (ZT, Zhangtang; AJS, Anjiashan; STS, Shuitaoshu).

Additional file 5: Figure S3. The wild rice sites. The three in situ natural reserve sites (A) AJSI, (B) STSI and (C) ZTI and three ex situ artificial protection nurseries (D) AJS, (E) STS and (F) ZT. (In Figure C, professor Dazhou Chen who is one of the initiators for Dongxiang wild rice conservation is observing the growth status of wild rice).

Additional file 1: Table S1. Statistics for the quality assessment of the sequencing data.

Additional file 3: Figure S1. The α-diversity of the (A, B) bacterial and (C, D) fungal communities in the rhizosphere of wild rice populations of the in situ natural reserves (ZTI, Zhangtang; AJSI, Anjiashan; STSI, Shuitaoshu) and ex situ (ZT, Zhangtang; AJS, Anjiashan; STS, Shuitaoshu).

Additional file 2: Table S2. Details of the sampling sites.

Background The soil microbiome drives soil ecosystem function, and soil microbial functionality is directly linked to interactions between microbes and the soil environment. However, the context-dependent interactions in the soil microbiome remain largely unknown. Results Using latent variable models (LVMs), we disentangle the biotic and abiotic interactions of soil bacteria, fungi and environmental factors using the Qinghai-Tibetan Plateau soil ecosystem as a model. Our results show that soil bacteria and fungi not only interact with each other but also shift from competition to facilitation or vice versa depending on environmental variation; that is, the nature of their interactions is context-dependent. Conclusions Overall, elevation is the environmental gradient that most promotes facilitative interactions among microbes but is not a major driver of soil microbial community composition, as evidenced by variance partitioning. The larger the tolerance of a microbe to a specific environmental gradient, the lesser likely it is to interact with other soil microbes, which suggests that facilitation does not necessarily lead to niche expansion.

The rhizomicrobial community is influenced by plant genotype. However, the potential differences in the co-assembly of bacterial and fungal communities between parental lines and different generations of rice progenies have not been examined. Here we compared the bacterial and fungal communities in the rhizomicrobiomes of female parent Oryza rufipogon wild rice; male parent Oryza sativa cultivated rice; their F1 progeny; and the F2, F3 and F4 self-crossing generations. Our results showed that the bacterial and fungal α-diversities of the hybrid F1 and self-crossing generations (F2, F3, F4) were closer to one of the two parental lines, which may indicate a role of the parental line in the diversity of the rhizosphere microbial community assembly. Self-crossing from F1 to F4 led to weak co-variation of the bacterial and fungal communities and distinct rhizosphere microbiomes. In the parental and self-crossing progenies, the reduction of community dissimilarity was higher for the fungal community than for the bacterial community.

Additional file 4: Table S4. The including predictors of final ECC prediction model.

Additional file 4: Table S4. The including predictors of final ECC prediction model.

Additional file 3: Table S3. The results of the candidate variables included in the LASSO regression and their corresponding coefficients for the different values of the penalty parameter λ.

Additional file 1: Table S1. The coding of variables.

Additional file 3: Table S3. The results of the candidate variables included in the LASSO regression and their corresponding coefficients for the different values of the penalty parameter λ.

Additional file 2: Table S2. Multivariable logistic regression analysis of factors associated with ECC positivity.

Microbial communities from rhizosphere (rhizomicrobiomes) have been significantly impacted by domestication as evidenced by a comparison of the rhizomicrobiomes of wild and related cultivated rice accessions. While there have been many published studies focusing on the structure of the rhizomicrobiome, studies comparing the functional traits of the microbial communities in the rhizospheres of wild rice and cultivated rice accessions are not yet available. In this study, we used metagenomic data from experimental rice plots to analyze the potential functional traits of the microbial communities in the rhizospheres of wild rice accessions originated from Africa and Asia in comparison with their related cultivated rice accessions. The functional potential of rhizosphere microbial communities involved in alanine, aspartate and glutamate metabolism, methane metabolism, carbon fixation pathways, citrate cycle (TCA cycle), pyruvate metabolism and lipopolysaccharide biosynthesis pathways were found to be enriched in the rhizomicrobiomes of wild rice accessions. Notably, methane metabolism in the rhizomicrobiomes of wild and cultivated rice accessions clearly differed. Key enzymes involved in methane production and utilization were overrepresented in the rhizomicrobiome samples obtained from wild rice accessions, suggesting that the rhizomicrobiomes of wild rice maintain a different ecological balance for methane production and utilization compared with those of the related cultivated rice accessions. A novel assessment of the impact of rice domestication on the primary metabolic pathways associated with microbial taxa in the rhizomicrobiomes was performed. Results indicated a strong impact of rice domestication on methane metabolism; a process that represents a critical function of the rhizosphere microbial community of rice. The findings of this study provide important information for future breeding of rice varieties with reduced methane emission during cultivation for sustainable agriculture.

With the continuous development of solar cells, the perovskite solar cells (PSCs), whose hole transport layer plays a vital part in collection of photogenerated carriers, have been studied by many researchers. Interface transport layers are important for efficiency and stability enhancement. In this paper, we demonstrated that lithium (Li) and cobalt (Co) codoped in the novel inorganic hole transport layer named NiOx, which were deposited onto ITO substrates via solution methods at room temperature, can greatly enhance performance based on inverted structures of planar heterojunction PSCs. Compared to the pristine NiOx films, doping a certain amount of Li and Co can increase optical transparency, work function, electrical conductivity and hole mobility of NiOx film. Furthermore, experimental results certified that coating CH3NH3 PbI xCl3&minus, x perovskite films on Li and Co- NiOx electrode interlayer film can improve chemical stability and absorbing ability of sunlight than the pristine NiOx. Consequently, the power conversion efficiency (PCE) of PSCs has a great improvement from 14.1% to 18.7% when codoped with 10% Li and 5% Co in NiOx. Moreover, the short-circuit current density (Jsc) was increased from 20.09 mA/cm 2 to 21.7 mA/cm 2 and the fill factor (FF) was enhanced from 0.70 to 0.75 for the PSCs. The experiment results demonstrated that the Li and Co codoped NiOx can be a effective dopant to improve the performance of the PSCs.

Polycyclic aromatic hydrocarbons (PAHs) and heavy metals are generally present in mixtures in the e-waste dismantling areas, posing serious health risk to the local people. Bioremediation has been considered as a promising approach for PAHs and heavy metals removal. In this study, we applied flow cytometry to obtain a better understanding of membrane potential (MP), apoptosis and cell cycle of Stenotrophomonas maltophilia affected by combined pollutants of benzo[a]pyrene(BaP) and Cu(II). The results showed that BaP was the main factor damaging the cell membrane and influencing the MP. S. maltophilia could even protect against upsetting situation by encouraging early apoptosis, whereby compromised cells committed suicide, as a result, which, in turn, facilitated the metabolism of the bacteria with high-vitality. Furthermore, even if the bacterial cell division was blocked and stopped reproduction, a large number of key enzymes inside cells could still be used for degradation of BaP. The expression of protein related to the transport and metabolism of BaP, regulation of redox reactions and phosphorylation in bacterial cell during bioprocess were evident different.

In the development process of a certain CHINA VI proprietary brand car model, there exists the problem of intermittent “dada” sound in the cockpit during idling. After investigation, it’s determined that the air pulse noise generated when the canister purge solenoid valve is working, it is transmitted to the car panels through the pipeline, and then to the cockpit, which would cause a “dada” sound. By adding expansion chamber in the desorption pipe and designing part of the pipeline which fixed in the clamp as rubber pipe, the intensity of air pulse can be effectively reduced and the transmission path of air pulse vibration can be blocked. Through objective testing and subjective evaluation, the scheme can greatly reduce the idle noise of the cockpit, thus improving the NVH performance of the vehicle and bringing comfortable riding environment to the passengers.

The past half century has seen an unprecedented growth of the world's urban population. Increasing urbanization and concern about sustainability and quality of life issues have produced considerable interest in air quality in urban areas. Urban ventilation implies that rural areas may supply relatively clean air into urban canopies and distribute rural air within them to help air exchange and pollutant dilution. This paper numerically studied rural air flow through square building arrays at different wind angles. The building area density ( λp , i.e. the rario between the plan area of buildings viewed from above and the total underlying surface area) is restricted to 0.25, while the building numbers in the square region change from 9 to 81. A two-dimensional (2D) k-ɛ turbulence model is employed to solve the Reynolds-averaged Navier-Stokes equations.The model is employed to predict the influence of the building numbers on flow capacity in wind angle altering from 0° - 45°. 3D model is employed to solve this problem as well. It's confirmed that fewer buildings get better flow capacity. Smaller wind angle improves this process as well.

AYDIN, METIN/0000-0003-3767-946X; Canamares, Maria Vega/0000-0001-8900-3125 WOS: 000272521700014 The normal Raman and surface-enhanced Raman scattering (SERS) spectra of flavanthrone and indanthrone were obtained at several excitation wavelengths. The spectral assignments were aided by density functional calculations. Since both molecules have very high symmetry (C-2h) including a center of inversion, we expect that the modes of u symmetry will be forbidden in the normal Raman spectrum. However, proximity to the surface causes special SERS enhancement of several of the b(u) modes, along with somewhat weaker enhancement of the a(u) and b(g) modes. Copyright (C) 2009 John Wiley & Sons, Ltd. National Institute of Justice [2006-DN-BX-K034]; City University Collaborative Incentive program [80209]; National Science Foundation under Cooperative AgreementNational Science Foundation (NSF) [RII-9353488, CHE-0091362, CHE-0345987, ECS0217646]; City University of New York PSC-BHE Faculty Research Award Program.; National Science FoundationNational Science Foundation (NSF) [IMR 0526926]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China [NSFC 20773045, 20627002]; Programme of Introducing Talent of Discipline to Universities [B06009] We are indebted to the National Institute of Justice (Department of Justice Award #2006-DN-BX-K034) and the City University Collaborative Incentive program (#80209). This work was further supported by the National Science Foundation under Cooperative Agreement No. RII-9353488, grant No. CHE-0091362, CHE-0345987 and grant number ECS0217646 and by the City University of New York PSC-BHE Faculty Research Award Program. We are also indebted to the National Science Foundation Grant # IMR 0526926, which supplied the Bruker Senterra/Ramanscope combined Dispersive Raman/FT Raman spectrometer. This work is also supported by the National Natural Science Foundation of China (NSFC 20773045 and 20627002) and the Programme of Introducing Talent of Discipline to Universities ('111' Project, B06009).