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The use of green manures contributes to sustainable soil and nutrient management in agriculture; however, the responses of soil microbial communities to different fertilization regimes at the regional scale are uncertain. A study was undertaken across multiple sites and years in Hunan, Jiangxi, Anhui, Henan, Hubei, and Fujian provinces of South China to investigate the effects of green manuring on the structure and function of soil bacterial communities in rice-green manure cropping systems. The study included four treatments: winter fallow with no chemical fertilizer as a control (NF), milk vetch as green manure without chemical fertilizer (GM), winter fallow and chemical fertilizer (CF), and a combination of chemical fertilizer and milk vetch (GMCF). Significant differences were found in the responses of soil microbial communities at different sites, with sampling sites explaining 72.33% (F = 36.59, P = 0.001) of the community composition variation. The bacterial communities in the soils from Anhui, Henan, and Hubei were broadly similar, while those from Hunan were distinctly different from other locations. The analysis of Weighted UniFrac distances showed that milk vetch changed soil microbial communities compared with winter fallow. Proteobacteria and Chloroflexi predominated in these paddy soils; however, the application of green manures increased the relative abundance of Actinobacteria. There was evidence showing that the functional microbes which play important roles in the cycling of soil carbon, nitrogen (N), and sulfur (S) changed after several years of milk vetch utilization (linear discriminant analysis score > 2). The abundance of methane-oxidizing bacteria and S-reducing bacteria increased, and microbes involved in N fixation, nitrification, and denitrification also increased in some provinces. We concluded that the application of milk vetch changed the bacterial community structure and affected the functional groups related to nutrient transformation in soils at a regional scale.

Rice straw (RS) was incorporated into paddy soil together with leguminous green manure (e.g., Chinese milk vetch, Astragalus sinicus L., MV) in a mesocosm-scale experiment and the enzyme activity and composition of main microbial groups were measured. Mixing MV and RS caused a synergistic release of residual C and N, leading to a low C/N ratio at the middle and late decomposition stages of the mixture and shortening the time to complete decomposition. Furthermore, the highest abundances of Gram-negative (G−) bacteria and fungi and the highest activities of α- and β-glucosidase, β-cellobiosidase, β-xylosidase, N-acetyl-glucosaminidase, and acid phosphomonoesterase were observed in the residue mixture, especially at the middle and late stages of the experiment. The residue decomposition rate was positively correlated with residual N and mineral N concentrations. Most hydrolases and both oxidase (phenol oxidase and peroxidase) activities, and G− bacterial (especially 18:1 ω5c, Photobacterium) abundance explained the decomposition of mixing residues. In conclusion, co-incorporation of MV and RS could stimulate their decomposition by retaining a relatively low C/N ratio, enhancing G− bacterial abundance and hydrolase activities. Introducing leguminous green manures in paddy fields may be an effective way to accelerate the decomposition of rice straw.

Soil cadmium (Cd) contamination is becoming a widespread concern because of its threat to global ecosystem health and food security. Co-incorporation of Chinese milk vetch (MV) and rice straw (RS) is a common agricultural practice in Southern China; however, the effects of combining these two materials with biochar on Cd bioavailability remain unclear. This study investigated the effects of MV, RS, rape straw biochar (RB), iron-modified biochar (FB), and their combinations on Cd uptake by rice through incubation and field experiments. The results showed that compared with the control without material input (CK), MV + RS (MR), MV + RS + RB (MRRB), and MV + RS + FB (MRFB) considerably reduced the Cd concentration in brown rice by 61.20 %, 65.38 %, and 62.65 %, respectively. Furthermore, the treatments increased the formation of iron‑manganese plaque (IMP) at different growth stages; MRRB and MRFB exhibited the highest increase rates among the treatments. Quantitatively, the Fe plaque and Mn plaque were increased by 20.61 %-47.23 % and 80.18 %-172.74 %, respectively. Compared with CK, the MRRB and MRFB treatments reduced the soil available Cd by 35.09 %-54.45 % and 38.20 %-50.20 %, respectively, at all stages. This decrease was substantially lower than that observed in the MV, RS, and MR treatments. Similar trends were observed in the incubation experiment. Additionally, the Community Bureau of Reference Sequential Extraction Analysis indicated that the MRRB and MRFB treatments converted the bioavailable Cd fractions into a stable form. Partial least squares path model and redundancy analysis revealed that pH was the major factor influencing Cd bioavailability. This study emphasized that the dual impact factors from the enhancement of Cd passivation capability and IMP formation jointly result in the reduction of Cd uptake by rice. Consequently, the co-incorporation of MV, RS, and biochar is promising for remediating Cd-contaminated paddy soils in Southern China.

Returning rice straw and leguminous green manure alone or in combination to soil is effective in improving soil fertility in South China. Despite the popularity of this practice, our understanding of the underlying processes for straw and manure combined application is relatively poor. In this study, rice straw (carbon (C)/nitrogen (N) ratio of 63), green manure (hairy vetch, C/N ratio of 14), and their mixtures (C/N ratio of 25 and 35) were added into a paddy soil, and their effects on soil N availability and C or N loss under waterlogged conditions were evaluated in a 100-d incubation experiment. All plant residue treatments significantly enhanced CO2 and CH4 emissions, but decreased N2O emission. Dissolved organic C (DOC) and N (DON) and microbial biomass C in soil and water-soluble organic C and N and mineral N in the upper aqueous layer above soil were also enhanced by all the plant residue treatments except the rice straw treatment, and soil microbial biomass N and mineral N were lower in the rice straw treatment than in the other treatments. Changes in plant residue C/N ratio, DOC/DON ratio, and cellulose content significantly affected greenhouse gas emissions and active C and N concentrations in soil. Additionally, the treatment with green manure alone yielded the largest C and N losses, and incorporation of the plant residue mixture with a C/N ratio of 35 caused the largest net global warming potential (nGWP) among the amended treatments. In conclusion, the co-incorporation of rice straw and green manure can alleviate the limitation resulting from only applying rice straw (N immobilization) or the sole application of leguminous green manure (high C and N losses), and the residue mixture with a C/N ratio of 25 is a better option because of lower nGWP.

Water-extractable organic matter (WEOM) plays an important role in many chemical processes and in soil organic matter accumulation. Large amounts of WEOM can be released by green manure when being ...

Background: Soil microbiome plays a crucial role in terrestrial ecosystem functions. However, its response to long-term fertilization and contribution to soil functions in agricultural ecosystems are unclear. Here, we investigated soil bacterial and fungal communities along vertical profiles (0 to 100 cm) and explored the importance of soil microbiome in controlling soil functions (soil multifunctionality and functionality of C, N, and P cycling) and nutrient cycling processes (C mineralization, N2O release, and biological N-fixation) in a 33-year field fertilization experiment. Results: We obtained solid evidence that long-term fertilization (with chemical N, cow manure, straw, and green manure) enhanced the soil functions compared with no fertilizer control and that the functionality of N cycling was significantly associated with crop production. Soil functions and nutrient cycling processes were more closely correlated with the relative abundance and diversity of keystone phylotypes within the global network than the entire soil microorganism community. These keystone phylotypes were positively associated with the absolute abundance of functional genes related to C, N, and P cycling, and they also contained many essential functional microbes involved in C mineralization, N2O release, and biological N-fixation. The application of chemical N, green manure, and cow manure showed the highest abundance of amoB, nifH, and GH48 genes and Nitrosomonadaceae, Azospirillaceae, and Sphingomonadaceae within keystone phylotypes, which were significantly and positively correlated with N2O release, biological N-fixation, and C mineralization, respectively. Moreover, our results suggested that organic fertilization improved the effects of network size and keystone phylotypes on subsoil functions by facilitating the migration of soil microorganisms across soil profiles.Conclusions: This study highlights the importance of relative abundance and diversity of keystone phylotypes in controlling soil functions and nutrient cycling processes after long-term fertilization, in addition to providing selectable fertilization strategies for regulating them in agricultural ecosystems.

This paper presents a new adaptive method forformation control of unmanned aerial vehicles (UAVs) withlimited leader information and communication. We study aformation control protocol in the framework of vector-fieldguidance where the leader can communicate its position andorientation but not its velocity. A practical motivation for thisscenario is the so-called congestion-aware control, in whichtrade-offs between the density of unmanned vehicles andcommunication interference caused by many communicatingvehicles arise: these trade-offs may require to reduce thecommunication load to avoid interference. To compensate forthe lack of knowledge of the leader velocity, each UAV makesuse of a local estimation mechanism. The resulting method isan adaptive control method, whose stability can be establishedusing Lyapunov stability. We show that the method can beextended to a distributed communication setting with a fewneighboring UAVs in place of the leader. Extensive simulationswith different formation shapes (Y, V and T formation) showthat the proposed adaptation mechanism effectively achieves theformation despite the unknown leader velocity. The proposedmechanism has a very similar performance to the ideal casewhen the leader velocity is perfectly known, and outperforms allthe non-adaptive cases in which the followers have an incorrectknowledge of the leader velocity.Keywords: Vector field, formation control, local estimation,unknown leader velocity, adaptive control.

We theoretically investigate the Goos-Hänchen (GH) shifts of reflected light beams in Thue-Morse photonic crystals. The systems are constituted by two Thue-Morse dielectrics multilayers and satisfy parity-time (PT) symmetry. Double coherent perfect absorption laser points (CPA-LPs) are achieved in the parameter space composed of the incident angle and the gain-loss factor. Dramatic changes in the phase of reflection coefficient induce giant positive and negative spatial GH shifts at the CPA-LPs, while great angular GH shifts exist around the exceptional points (EPs). The spatial GH shifts present non-reciprocity for the forward and backward incident light waves near the double CPA-LPs, while the angular GH shifts are quasi-reciprocal. Increasing the Thue-Morse sequence number, these characteristics are approved around multiple CPA-LPs as well. Our work could pave the way to explore high-accuracy optical sensors.

Hypertension and hyperhomocystinemia have a joint effect on the risk of stroke. We aimed to evaluate the relationship between plasma total homocysteine (tHcy) and blood pressure in two independent Chinese populations. Four thousand five hundred and fifty-five participants who underwent health examinations between March 2016 and September 2016 at Peking University First Hospital were enrolled as ‘Population 1’, and 2689 participants who were admitted to Peking University First Hospital between January 2014 and December 2015 were enrolled as ‘Population 2’. None of the study participants were taking antihypertensive medication or vitamins, or had cardio-cerebrovascular disease or chronic kidney disease stages 4 or 5. In Population 1, a 5 μmol/L increase in tHcy was associated with a 0.47 mmHg (95% confidence interval [CI]: 0.23–0.70 mmHg, p

In this paper, analytical solutions of period-1 motion of a first-order quadratic nonlinear system with both parametric excitation and external excitation are investigated through the generalized harmonic balance method. The analytical solutions of the system are obtained via solving the coefficients of all harmonic terms at the equilibrium position. The precision of analytical solutions is guaranteed via convergence study of harmonic balance terms. Stability analysis is carried out via eigenvalue analysis. The analytical solutions are different from the perturbation analysis solutions. Moreover, the trajectories of periodic motions obtained from analytical solutions can better explain the dynamics of the system. To verify the accuracy of analytical solutions, numerical simulation are performed and the simulation results are compared with the analytical solutions. The harmonic spectra are also presented to illustrate of the contribution of each harmonic term on a periodic motion.

The Goos-Hänchen (GH) effects are investigated for a transverse magnetic beam totally reflected by periodic PT-symmetric photonic crystals. A dielectric layer with a real refractive index situates as a defect in the center. Both positive and negative spatial GH shifts are induced around the defect mode. The GH shifts sensitively change with the refractive index of the defect layer. More importantly, giant negative GH shift effect with big reflectance could be found and modulated by increasing the gain-loss factor in PT-symmetric systems, which could improve the detecting sensitivity of the defect. Our study may be valuable in potential applications for highly sensitive sensors.

The legume species

Quadrotors are making a difference to numerous civilian and military applications. There are various approaches to realize formation flight control. In this paper, a comparison between sliding mode and second-order consensus approaches for quadrotor leader-follower formation flight was conducted. Sliding mode and second-order consensus algorithms were employed to design the formation controller for steady formation flight. Both leader and the follower quadrotors are controlled by proportional integral derivative controllers. The leader follows the desired trajectory while the followers follow the instruction calculated by the formation controller. Simulations are carried out to analyze the effect of these two approaches. The result indicates that the followers can follow the leader's trajectory and keep the formation fairy well under the control of both approaches. However, the sliding mode approach can achieve faster position convergence effect, while the second-order consistency approach has better disturbance suppression performance in case of disturbance.

The co-incorporation of rice straw (RS) and milk vetch (MV) into paddy fields has been increasingly applied as a sustainable farming practice in southern China. Our previous study revealed the contribution of bacteria to the co-decomposition of the RS and MV mixture, although additional underlying factors driving the co-decomposition process need to be clarified. The present study further determined the succession of fungal communities and enzyme activity in the co-decomposition process of the RS and MV mixture. The results showed that non-additive synergistic effects on biomass loss were observed in 55.6% of the sampled RS and MV mixture during the co-decomposition process, stimulating mixture decomposition. Overall fungal abundance was 19.6-30.6% higher in the RS and MV mixture throughout the study than in the single residue. Fungal diversity and community structure were mainly affected by the sampling date rather than the type of residue. Specifically, mixing RS and MV significantly increased the abundance of Peziza sp. and Reticulascus tulasneorum (lignocellulose- and lignin-decomposing fungi) and exhibited higher activities of C- and N-related hydrolases than monospecific residues. Random forest (RF) models showed that bacteria contributed more to the residue decomposition and activities of C-related hydrolases, N-related hydrolases, and oxidases than fungi. However, both RF and partial least squares path models revealed that fungal abundance and community structure directly or indirectly affected the residue decomposition rate. These findings showed that mixing RS and MV could stimulate their decomposition by enhancing C-related hydrolase activity and Peziza sp. and Reticulascus tulasneorum abundance.

The privacy protection and information security are two crucial issues for future advanced artificial intelligence devices, especially for cooperative system with rich core data exchange which may offer opportunities for attackers to fake interaction messages. To combat such threat, great efforts have been made by introducing trust mechanism in initiative or passive way. Furthermore, blockchain and distributed ledger technology provide a decentralized and peer-to-peer network, which has great potential application for multi-agent system, such as IoTs and robots. It eliminates third-party interference and data in the blockchain are stored in an encrypted way permanently and anti-destroys. In this paper, a methodology of blockchain is proposed and designed for advanced cooperative system with artificial intelligence to protect privacy and sensitive data exchange between multi-agents. The validation procedure is performed in laboratory by a three-level computing networks of Raspberry Pi 3B+, NVIDIA Jetson Tx2 and local computing server for a robot system with four manipulators and four binocular cameras in peer computing nodes by Go language.

Due to the nature of complexity, inflexibility and non-robustness of classical cooperative control algorithms, the deep reinforcement learning has been widely researched and applied in collective and continuous behaviour control. Especially for multi-agents in real world, acquiring a full view world with a quick learning is still a great challenge. Inspired by Policy Gradient (PG) and its successors, a toy model with multi-agents by four two-dimensional manipulators environment is built based on physics engine-based MuJoCo. With a modified deep deterministic policy gradient algorithm and different credit strategies for individual agent, the cooperation and competition behaviour to target location between agents are studied. The experimental results show that each robot can complete the task with a negligible convergence effect, indicating that the MADDPG algorithm has a good performance in a complex environment, and successfully learn the strategy of multi-agent collaboration. However, with the instability of the environment caused by the increase in the number of agents, deep reinforcement learning has certain difficulties in the joint action space.

The traditional two-level and three-level converters have their own disadvantages when the energy does not need to flow bidirectionally. In this paper, the topological structure and working principle of the three-level three-switch VIENNA rectifier are deeply analyzed. In view of the fluctuation of dc-side neutral-point potential in VIENNA rectifier, dc bus capacitor voltage deviation is introduced into duty cycle allocation of SVPWM. The neutral-point potential balance is achieved by adjusting the action time of each vector. A simplified SVPWM modulation algorithm for three-level to two-level is studied. Finally, a simulation model is built in Matlab/Simulink. The simulation results verify the feasibility of simplified SVPWM modulation algorithm and neutral-point potential balance control strategy.

In this paper, a class of three dimensional nonlinear chaotic dynamic systems, which have only one equilibrium position, are studied. The least conservative linear feedback control is introduced to make the systems globally exponentially stable. For four kinds of nonlinear chaotic systems, Sport D, I, J, L presented in reference [1], since the correlation of three equations in each system are good enough, it is relatively easy to realize linear feedback to achieve the aim of controlling chaos. Simulations are proposed to verify the good performance of the controlled systems with the given linear controllers.

We studied the effects of mixing rice straw and hairy vetch plant residues in a subtropical paddy soil, on subsequent carbon (C) and nitrogen (N) dynamics. Using a theoretical framework, we designed two groups of experiments (involving equal amounts of residual C or N addition, referred to as either C or N treatments). Each experiment included mixed residues of rice straw and hairy vetch at different mixing ratios. Soils together with residues were incubated at 25 °C under waterlogged conditions for 100 days. Greenhouse gas (GHG) emissions and soil C and N fractions were measured continuously. Both C and N treatments affected soil C and N dynamics, and these dynamics were quantitatively dependent on residue C/N ratios. The effect of residue mixtures on C and N dynamics could not be predicted from single residues, since there were non-additive effects of residue mixtures. Synergistic effects were generally more frequent than antagonistic effects. Residue mixtures tended to enhance CO2 and CH4 emissions in both C and N treatments but decreased N2O emissions in the N treatment. In the N treatment, dissolved organic C (DOC), dissolved organic N (DON), and microbial biomass C (MBC) concentrations increased. DOC and DON concentrations decreased in the C treatment. Residue mixtures enhanced the global warming potentials (GWP) of greenhouse gases (GHG) emitted from soil by non-additive synergistic effects. The C/N ratio of residue mixtures affected the non-additive responses of soil C and N dynamics, for example mixtures with a C/N ratio of 25 had higher CO2 emissions and DOC concentrations than those with a C/N ratio of 35 as a consequence of non-additive effects, however, CH4 emissions and MBC concentrations were higher in mixtures with a C/N ratio of 35 than in mixtures with a C/N ration of 25. These results indicated that non-additive effects can impact soil C and N dynamics and that residue C/N ratios play an important role in influencing non-additive effects. Applying a single residue to paddy soils may be better than residue mixtures from a GWP mitigation perspective.

To ensure the photovoltaic (PV) arrays under partial shading condition(PSC) could still output maximum power quickly and efficiently, this work presents a modified hybrid maximum power point tracking (MPPT) method, which applies artificial neural network (ANN) to the modified perturb and observe (MP&O). Instead of using expensive illumination intensity sensors directly, the illumination intensity on each module in the PV array can be obtained indirectly by sampling the specific points of their own cheaper voltage-current sensors. ANN uses indirect illumination intensity to predict the optimal voltage areas of the global maximum power point (GMPP). Based on the areas, MP&O adopts a adaptive step size strategy to obtain GMPP. By modeling and simulation in Matlab/Simulink, it is shown that the tracking time and efficiency of the proposed method in this work can reach 0.026s and 99.87% respectively. Compared with other methods, the method has faster speed, higher efficiency, smaller fluctuation and lower complexity.

Water-extractable organic matter (WEOM) plays an important role in many chemical processes and in soil organic matter accumulation. Large amounts of WEOM can be released by green manure when being incorporated into the soil. However, the characteristics of WEOM extracted from different green manures (GMs) are unclear. In this study, WEOM samples were extracted from Chinese milk vetch (

The legume species Astragalus sinicus (Chinese milk vetch, CMV) has been widely cultivated for centuries in southern China as one of the most important green manures/cover crops to improve rice productivity and prevent soil degeneration. In this study, we generated the first chromosome-scale reference genome of CMV using a combination of PacBio, Illumina sequencing, and high-throughput chromatin conformation capture(Hi-C) technology. The CMV genome was 595.52 Mb, with a contig N50 size of 1.50 Mb. Long terminal repeats (LTR) were amplified and contributed to the genome size expansion in CMV. CMV underwent two whole-genome duplication (WGD) events, and the retained genes following WGD, which were shared by Papilionoideae species, shaped the hormonal regulation of nodulation and the symbiosis with rhizobia. The chalcone synthase (CHS) gene family was expanded and expressed primarily in the root of CMV. Intriguingly, we found that R genes were highly expressed in root than in the nodules of legume species, suggesting that they may be hired to increased plant immunity in root to cope with pathogen infection in legume species. Our work sheds light on the genetic basis of nodulation and symbiosis in CMV and provides a benchmark for accelerating genetic research and molecular breeding in the future.

The danger posed by cadmium (Cd) pollution to rice production is continuously increasing. Co-utilizing milk vetch (Astragalus sinicus L.) and rice straw is a good practice for rice yield and soil fertility in south China. However, its effects on Cd availability in soil–rice systems remain unclear. A micro-plot trial of two typical paddy soils (alluvial sandy soil and reddish clayey soil) in south China was conducted to investigate the effects of milk vetch, rice straw, lime, and their combined application on Cd availability and the related mechanisms. Soil chemical properties, CaCl2-extractable Cd (CaCl2-Cd), total content of Cd (Total-Cd), Cd fractionation (BCR sequential-extraction method), and Cd accumulation in rice were measured. Results showed that the co-utilization of milk vetch, rice straw, and lime (GRFL) decreased the Cd content in rice grain by 91.43% and 15.63% in early rice of two soils, respectively. Cd was not detected in late rice grains. CaCl2-Cd decreased by 0.025 mg kg−1 in late rice of alluvial sandy soil, 0.057 and 0.044 mg kg−1 decreased in early and late rice of reddish clayey soil, and Total-Cd decreased by 19.4% and 9.1% for early rice of two soils, respectively. Co-utilizing milk vetch, rice straw, and lime changed the distribution of different chemical forms of Cd, decreased the content of bioavailable Cd in soil by reducing the Aci-Cd and Red Cd, and benefited the formation of more stable residual fraction (Res Cd). Redundancy analysis showed that the improvement in soil pH, dissolved organic matter (DOM), and other soil properties was the main cause of the transformation of Cd form. Among the soil properties, pH and DOM had the greatest impacts on Cd availability. In conclusion, co-utilizing milk vetch and rice straw can alleviate the danger of soil Cd in rice production, and this effect could be strengthened by applying lime.

The aim of this study was to compare the toxicity effects of carbon nanomaterials (CNMs), namely fullerene (C60), reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs), on a mini-ecosystem of rice grown in a loamy potted soil. We measured plant physiological and biochemical parameters and examined bacterial community composition in the CNMs-treated plant–soil system. After 30 days of exposure, all the three CNMs negatively affected the shoot height and root length of rice, significantly decreased root cortical cells diameter and resulted in shrinkage and deformation of cells, regardless of exposure doses (50 or 500 mg/kg). Additionally, at the high exposure dose of CNM, the concentrations of four phytohormones, including auxin, indoleacetic acid, brassinosteroid and gibberellin acid 4 in rice roots significantly increased as compared to the control. At the high exposure dose of MWCNTs and C60, activities of the antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD) in roots increased significantly. High-throughput sequencing showed that three typical CNMs had little effect on shifting the predominant soil bacterial species, but the presence of CNMs significantly altered the composition of the bacterial community. Our results indicate that different CNMs indeed resulted in environmental toxicity to rice and soil bacterial community in the rhizosphere and suggest that CNMs themselves and their incorporated products should be reasonably used to control their release/discharge into the environment to prevent their toxic effects on living organisms and the potential risks to food safety.

BackgroundIn the beginning of January 2020, new unknown virus pneumonia cases started to emerge in local hospitals in Wuhan, China. This virus epidemic quickly became a public health emergency of international concern by the WHO. Enormous amount of medical supplies as well as healthcare personals from other provinces were mobilized to support Wuhan. This current work tent to help people understanding how infectious disease spread and the purpose and consequences of various efforts based on simulation model.Methoda simulation model was created using known parameters. R0 set to 3 and mean incubation time to be 7.5days. the epidemic was divided to 3 periods. Simulation would run 50 times to mimic different patient0 status. Personal activity index was used to mimic different level of control measures. 141427709 simulated patients were created. Cumulation number of patients at the end of period 1 (day50) is 2868.7±1739.0. Total infected patients could be 913396.5 ± 559099.9 by the end of period 2 (day70) in free transmission state. And at day90, total patients number is 913396.5 ± 559099.9.ConclusionCOVID-19 is a novel severe respiratory disease. This will put great burden on the shoulder of healthcare workers as well as on medical hardware and supplements. Current strict control measures help to contain disease from spreading. An early detecting, reporting and fast reacting system needs to be setup to prevent future unknown infectious disease.

The practice of co‐incorporating rice straw and leguminous green manure (such as Chinese milk vetch) into paddy soils has become increasingly popular in the last 10 years, although its effect on soil CH₄ emissions and microbial community structure is poorly understood. In this study, data from a 2‐year pot experiment were used to reveal the effects of the co‐incorporation of rice straw and Chinese milk vetch on CH₄ emissions and methanogenic and methanotrophic communities in paddy soil. Five treatments were chosen: CK (unamended control), CF (inorganic fertilizer), FM (inorganic fertilizer and Chinese milk vetch, 20 g 10 kg⁻¹ dry soil, 4.5 t ha⁻¹), FR (inorganic fertilizer and rice straw, 20 g 10 kg⁻¹ dry soil, 4.5 t ha⁻¹) and FMR (inorganic fertilizer and Chinese milk vetch and rice straw mixture, 5 + 15 g 10 kg⁻¹ dry soil, 1.125 + 2.375 t ha⁻¹). Overall, the soil CH₄ emissions in the 2 years under all residue treatments (104.4–122.8 and 83.3–133.3 g CH₄ m⁻²) were higher than those in CK (57.0 and 20.7 g CH₄ m⁻²) and CF (71.8 and 21.9 g CH₄ m⁻²) treatments. The FMR treatment decreased CH₄ emissions when compared with FM and FR, especially in the second year. A higher abundance of methanogens (mcrA gene copies) was found under the plant residue‐treated soils (4.35 × 10⁸ g⁻¹ dry soil on average) and FM increased the abundance of methanotrophs (pmoA gene copies, 2.68 × 10⁶ g⁻¹ dry soil). Application of plant residues changed the methanogenic and methanotrophic community structures in comparison with CF (e.g., markedly increased the populations of Methanobacteriales and Methylomonas and suppressed Methanomicrobiales and Methylobacter populations). Methane emissions were significantly and positively related to the mcrA and pmoA gene copy numbers, as well as the mcrA/pmoA ratio. The partial least squares path model (PLS‐PM) indicated that the rice plant biomass (path coefficient = 0.64), the abundance of methanogens (path coefficient = 0.57) and the community structure of methanotrophs (path coefficient = −0.59) were determinants of CH₄ emissions. Among the three residue‐treated soils, FMR showed the lowest CH₄ emissions and was associated with a slight decrease in the mcrA/pmoA ratio and a significant increase in the Type I/Type II methanotrophs ratio. Thus, we recommend the co‐incorporation of Chinese milk vetch and rice straw as a sustainable fertilization pattern to improve the growth of rice and minimize CH₄ emissions. HIGHLIGHTS: Residue application improves rice productivity (except for FR), soil fertility and CH₄ emissions. Co‐incorporation of MV and RS reduces CH₄ emissions in comparison with pure MV or RS addition. Residue application changes the community structure of methanogens and methanotrophs. The methanogenic abundance and the methanotrophic community structure determine the CH₄ emissions.

This paper considers the consensus problem of multi-agent systems with time delay under directed topology. A novel proportional-integral (PI) control protocol with a time delay is proposed for each agent to ensure the consensus. The problem of consensus is converted to a stability problem by system transformation. Sufficient conditions are obtained based on the proposed Lyapunov functional candidate using Lyapunov stability theory, graph theory and matrix theory. The proposed condition has less conservatism by adding a triple-integral term. Finally, numerical simulations are provided to illustrate the effectiveness of the results.

In this paper, the analytical solutions for the period-1 motion of a cubic nonlinear dynamical system with two periodic forced terms are obtained through the generalized harmonic balance method. From the method, the analytical solutions are transformed to the Fourier series expansion in all harmonic terms at the equilibrium position. The stability and bifurcation analysis are investigated through eigenvalues analysis, and the accuracy of the analytical solutions is verified by numerical simulations. The harmonic amplitude distributions are presented to show the characteristic of the different-order terms with different excitation frequencies. From this study, the system parameters that make the system stable are determined. Furthermore, the robustness of the system is guaranteed by selecting the parameters appropriately.

A rapid monitoring platform for sensitive voltammetric detection of thiamethoxam residues is reported in the present study. A β-cyclodextrin-reduced graphene oxide composite was used as a reinforcing material in electrochemical determination of thiamethoxam. Compared with bare glassy carbon electrodes, the reduction peak currents of thiamethoxam at reduced graphene oxide/glassy carbon electrode and β-cyclodextrin-reduced graphene oxide/glassy carbon electrode were increased by 70- and 124-fold, respectively. The experimental conditions influencing voltammetric determination of thiamethoxam, such as the amount of β-cyclodextrin-reduced graphene oxide, solution pH, temperature, and accumulation time, were optimized. The reduction mechanism and binding affinity of this material is also discussed. Under optimal conditions, the reduction peak currents increased linearly between 0.5 µM and 16 µM concentration of thiamethoxam. The limit of detection was 0.27 µM on the basis of a signal-to-noise ratio of 3. When the proposed method was applied to brown rice in a recovery test, the recoveries were between 92.20% and 113.75%. The results were in good concordance with the high-performance liquid chromatography method. The proposed method therefore provides a promising and effective platform for sensitive and rapid determination of thiamethoxam. Environ Toxicol Chem 2017;36:1991-1997. © 2017 SETAC.

Conventional flux-reversal permanent-magnet (FRPM) machines suffer from large pole leakage flux, which leads to the poor utilization of PMs and reduction of main flux. This paper proposes a consequent-pole FRPM machine, whose magnet usage is halved compared with that of a conventional FRPM machine. Nevertheless, due to the reduction of the pole leakage flux, the proposed machine exhibits larger back EMF and torque than that of the conventional one. In this paper, the operation principles and mechanism of reduced pole leakage flux of the proposed machine are introduced. Moreover, with the employment of finite-element analysis, the electromagnetic performances of the proposed machine are evaluated and quantitatively compared with a conventional FRPM machine in terms of airgap flux density, flux linkage, back EMF, pulsating torque, rated torque, losses, and flux-weakening and overload capabilities.

Conventional low-temperature superconducting (LTS) machines have rather large short-circuit currents, and their peak fault current can reach 15 p.u., which is almost four times that of regular permanent-magnet machines. Vernier machines are well known for their big synchronous inductance, which is useful for reducing the peak current during a short-circuit fault. Moreover, their torque densities are higher compared to conventional synchronous machines due to the magnetic gearing effect. Thus, the purpose of this paper is to introduce a vernier concept to the LTS machine, i.e., a dual-stator vernier LTS machine, which can provide large torque density, as well as small short-circuit current and torque. The proposed machine has two stators and a sandwiched rotor which has spoke-array superconducting magnets. Based on the finite-element analysis, the pole ratio, split ratio, slot opening width, and slot depth of the proposed machine are optimized for a maximum obtainable torque, respectively. Moreover, the short-circuit performances of the LTS vernier machine are investigated and compared to that of a regular LTS machine. It is found that the proposed machine can dramatically reduce the peak current and peak torque during a symmetrical three-phase short-circuit fault, and its rated torque is also higher than that of the regular machine.

The present study determined the dynamic changes of enzyme activity and bacterial community in rice straw (RS) and milk vetch (MV) co-decomposing process. Results showed that mixing RS and MV promoted decomposition. The mixture enhanced β-glucosidase and β-cellobiohydrolase activities relative to its monospecific residue during the mid-late stage of decomposition. The mixture enhanced Enterobacteriaceae (monosaccharide decomposing bacteria) abundance during the initial stage of decomposition, and the abundance of Hydrogenispora, Bacteroides, Ruminiclostridium, and Acidobacteriaceae that could hydrolyze fiber during the mid-late stage of decomposition relative to single RS and MV, respectively, which would benefit mixture decomposition. Furthermore, more interconnected and competitive relations existed between the bacteria in the mixture. These results indicated that mixing RS and MV promoted residue decomposition by increasing hydrolytic enzyme activities and changing bacterial community. This study concluded that co-incorporating RS and MV may be recommended as a promising practice for the efficient utilization of RS resources.

Rice–rice–green manure rotations in south China are characterized by high efficiency and good environmental performance, and the application of green manure plays an important role in N management. Nitrification is a key process in N cycling and is highly correlated with the N utilization of crops and with leaching losses. As a potential N loss pathway, the nitrification process and nitrifiers as affected by green manuring are of critical importance. A pot experiment covering green manure-double rice rotation was conducted to evaluate the effects of green manure and N fertilizer on soil nitrification and to achieve a mechanistic understanding of underlying processes in an alkaline paddy soil. Soil nitrification potential (NP) and the recovered nitrification potential (RNP) were measured. Relative contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in soil nitrification were studied using specific bacterial inhibitors. In the alkaline paddy soil, soil NP and nitrate concentrations were significantly decreased by green manuring but increased with increasing N fertilization. Soil nitrification was dominated by AOB and that the relative contributions of AOB to RNP ranged from 65% to 79% at different sampling stages despite the larger abundance of AOA amoA gene numbers. RNP and the contribution of AOB to RNP were significantly increased by N fertilizer, whereas the contribution of AOA was decreased by green manuring. We concluded that the application of inorganic N enhanced NP while green manures reduced it, which is consistent with the variation of observed soil nitrate concentrations. These results indicate that the utilization of winter green manure is an effective practice to improve N management in paddy rice.

The interface polarization are of great important for electromagnetic wave absorption (EWA). However, the tailored interfacial structure and corresponding effect on EWA remain a huge challenge. Here, a novel strategy of constructing interfacial hierarchical structure is reported to unveil such basic relationship. The melamine carbonized sponge (MCS) composites with interfacial hierarchical structure are successfully synthesized under the assistance of trace amounts of nickel metal catalysis. The as-prepared MCS composites present adjustable microwave absorption performance with carbonization temperature increasing from 600 to 900 °C. Experimental and simulation results reveal the excellent EWA benefitting from appropriate interface polarization. Moreover, the model of interface polarization in dielectric behaviors is proposed. As a result, the interface factor, β, is found to be a key factor to balance interface polarization. Remarkably when the value of β is optimized to 0.3, MCS8 (carbonized at 800 °C) achieves ultralight (5.36 mg cm−3) and strong absorption (reflection loss of −76.59 dB). This work also provides a novel and feasible idea for rational design and application of interfacial hierarchical structure toward high-performance carbon absorbing materials with low density.

Figure S1. Schematic diagram of the simulated unit cell of AuNM on PET. (a) Top view. (b) Perspective view. Figure S2. Schematic diagram of the simulated models. (a) AuNM. (b) AuNM on PET. Figure S3. The potential distribution map of AuNM at constant current. Figure S4. The stress distribution map of the AuNM electrodes during bending simulation under 1.5 Ă 109N/m2 force at the Y direction. (DOC 1287 kb)

The cultivation of green manure or rice straw returns in southern China increases crop yields and soil fertility. Few studies have reported the effects of combining both management techniques on rice performance and soil fertility. A 3-year field study was carried out to analyse the impacts of the co-incorporation practice on soil microbial and biochemical parameters as well as crop yield. Five treatments were tested: (i) no-fertilizer (CK); (ii) chemical fertilizer (F); (iii) F plus green manure (FM); (iv) F plus rice straw (FS); (v) F plus green manure plus rice straw (FMS). The results showed that incorporation of green manure and/or rice straw increased double rice yields by 4.1% (FM), 4.7% (FS) and 9.6% (FMS) compared with F. The FMS treatment enhanced soil organic C (SOC), total N (TN), mineral N (Nₘᵢₙ), and available K (AK) levels by combining the advantage of FM in increasing TN and Nₘᵢₙ and the advantage of FS in increasing SOC and AK in comparison with F. The incorporation of green manure and/or rice straw stimulated microbial growth (total phospholipid fatty acids, PLFAs) and altered the soil microbial community structure relative to F, in which FMS had the greatest effect. The enzyme activities of β-glucosidase, β-cellobiosidase, N-acetyl-glucosaminidase, L-leucine aminopeptidase and phosphatase were higher in the green manure and/or rice straw application treatments than in the F treatment in the order FM ≈ FS

Although rice straw return is widely recommended for maintaining or improving soil fertility and rice yields, it inevitably increases methane (CH4) emissions. Effective measures to mitigate CH4 emissions while guaranteeing grain yields are urgently needed. A 2-year mesocosm experiment was conducted. Six management systems, i.e., no residue (traditional management, CF), 100% rice straw (a popular practice among farmers, FR), 50% rice straw (F1/2R), leguminous green manure (FM), mixture of leguminous green manure and 100% rice straw (FMR), and a mixture of leguminous green manure and 50% rice straw (FM1/2R), were used. Compared with the CF, the organic residue returns could effectively improve rice productivity but increase the CH4 emissions. Notably, when compared with the FR, both F1/2R and FM could reduce the CH4 emissions, with equal crop yields, and FM1/2R not only increased the rice yields but also reduced the CH4 emissions, whereas FMR increased the rice yields and the CH4 emissions. Applications of organic residues significantly increased the soil methane production potentials (MPPs), methane oxidation potentials (MOPs), the abundances of methanogens and methanotrophs, and changed methanogenic and methanotrophic community structures in comparison with the CF. The partial least squares path model (PLS-PM) results showed that the MPPs had a strong direct effect on CH4 emissions, whereas an abundance of methanogens could serve as a proxy for predicting CH4 emissions. Moreover, relatively high MOPs associated with high Type I/Type II methanotroph ratios and relatively low dissolved organic carbon (DOC) concentrations were found to be central in lowering CH4 emission fractions under the F1/2R and FM1/2R treatments. Above all, the combined utilization of leguminous green manure and rice straw exhibited potential prospects for the enhancement of rice yields and for the mitigation of CH4 emissions, and the practice of mixing leguminous green manure with 50% rice straw performed the best of the treatments tested.

Aiming at the problem that communication constraint and the states of agents restricted, distributed convex optimization algorithm for multi-agent network with state quantization is proposed. Firstly, considering communication constraint, the sampled-data model of closed-loop system is formulated. Then, considering convex inequalities with some set constraints, a corresponding control protocol is designed for all agents to drive to the intersection of all convex sets of the agents to reach a consensus through local interactions. By using the analysis method of Lyapunov theory and graph theory, conditions associated with connectivity are derived for all agents to come to an agreement when the network is strongly connected. Finally, a simulation example shows the availability of the proposed method.

In this paper, analytical solutions of periodic motions in a 1-D nonlinear dynamic system with two periodic excitation forces are obtained through the generalized harmonic balance method with prescribed-computational accuracy. From this method, the dynamic system is transformed to a nonlinear dynamic system of coefficients in the Fourier series. The analytical solutions of periodic motions are obtained by equilibriums of the coefficients dynamical system, and the corresponding stability analysis is carried out via eigenvalues analysis. With different excitation frequencies, the frequency-amplitude characteristics of periodic motions are analyzed.

With the development of society and economy, people pay more attention to their own health. The demand of more personalized health service is gradually rising. However, due to the lack of experienced doctors and physicians, most healthcare organizations cannot meet the medical demand of public. With the widespread use of hospital information system, there is huge amount of generated data which can be used to improve healthcare service. Thus, more and more data mining applications are developed to provide people more customized healthcare service. In this paper, we propose an AI-assisted prediction system, which leverages data mining methods to reveal the relationship between the regular physical examination records and the potential health risk. It can predict examinees' risk of physical status next year based on the physical examination records this year. The system provides a user-friendly interface for examinees and doctors. Examinees can know their potential health risks while doctors can get a set of examinees with potential risk. It is a good solution for the mismatch of insufficient medical resources and rising medical demands.

In this paper, a nonlinear model for genetic regulator networks (GRNs) with SUM regulatory logic is presented. Four sufficient and necessary conditions of global asymptotical stability and global exponential stability for the equilibrium point of the GRNs are proposed, respectively. Specifically, three weak sufficient conditions and corresponding corollaries are derived by using comparing theorem and Dini derivative method. Then, a famous GRN model is used as the example to illustrate the effectiveness of our theoretical results. Comparing to the results in the previous literature, some novel ideas, study methods and interesting results are explored.

This paper is concerned with the regularity criterion of weak solutions to the three-dimensional Navier-Stokes equations with nonlinear damping in critical weakLqspaces. It is proved that if the weak solution satisfies∫0T∇u1Lq,∞2q/2q-3+∇u2Lq,∞2q/2q-3/1+ln⁡e+∇uL22ds<∞, q>3/2, then the weak solution of Navier-Stokes equations with nonlinear damping is regular on(0,T].

Encrypted traffic identification has great significance to regulate illegal data, detect network attacks and protect users' information. Here we propose a novel approach to fast identify encrypted traffic via large-scale sparse screening. We investigate randomness features using Lasso regression to select the most relevant features. To make it more efficient to solve large-scale problems, we employ Enhanced Dual Polytope Projections(EDPP) screening rule to remove irrelevant features quickly. The identification is performed with the help of Extreme Learning Machine (ELM) because of its better identification and faster speed. Experimental results show that the method is efficient and effective in encrypted traffic identification.