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In nature, plants are exposed to a dynamic light environment. Fluctuations in light decreased the photosynthetic light utilization efficiency (PLUE) of leaves, and much more severely in C4 species than in C3 species. However, little is known about the plasticity of PLUE under dynamic light in C4 species. Present study focused on the influence of planting density to the photosynthesis under dynamic light in maize (Zea mays L.), a most important C4 crop. In addition, the molecular mechanism behind photosynthetic adaptation to planting density were also explored by quantitative proteomics analysis. Results revealed that as planting density increases, maize leaves receive less light that fluctuates more. The maize planted at high density (HD) improved the PLUE under dynamic light, especially in the middle and later growth stages. Quantitative proteomics analysis showed that the transfer of nitrogen from Rubisco to RuBP regeneration and C4 pathway related enzymes contributes to the photosynthetic adaptation to lower and more fluctuating light environment in HD maize. This study provides potential ways to further improve the light energy utilization efficiency of maize in HD. Summary statement: 1.As planting density increases, maize leaves receive less light that fluctuates more.2.The maize grown at high density improved the light utilization efficiency under dynamic light, especially in the middle and later growth stages.3.The transfer of nitrogen from Rubisco to RuBP regeneration and C4 pathway related enzymes contributes to the photosynthetic adaptation to lower and more fluctuating light environment in maize grown at high density. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide, ammonia, formaldehyde, toluene, n-pentane and acetone were used as indoor gas pollutants. Using ozone synergistic photocatalysis technology, Ti02 was selected as photocatalyst and doped with Fe3+, and the effects of TiO2 modification and different gas flow rate, initial reactant concentration, relative humidity and ozone concentration on purification efficiency were investigated. The results show that when the gas flow rate in the reaction section is 1 m/s,the amount of ozone is 49.08 mg/m³, the relative humidity is less than 50%, and the system runs for 30 min, the average purification efficiency of 03/Fe-Ti02/UV technology for six kinds of gas pollutants is 65%. [ABSTRACT FROM AUTHOR]

Rhodium-catalyzed cycloaddition reaction was calculated by density functional theory M06-2X method to directly synthesize benzoxepine and coumarin derivatives. In this work, we conducted a computational study of two competitive mechanisms in which the carbon atom of acetylene or carbon monoxide attacked and inserted from two different directions of the six-membered ring reactant to clarify the principle characteristics of this transformation. The calculation results reveal that: (i) the insertion process of alkyne or carbon monoxide is the key step of the reaction; (ii) for the (5+2) cycloaddition reaction of acetylene, higher energy is required to break the Rh−O bond of the reactant, and the reaction tends to complete the insertion from the side of the Rh−C bond; (iii) for the (5+1) cycloaddition of carbon monoxide, both reaction paths have lower activation free energy, and the two will generate a competition mechanism. [ABSTRACT FROM AUTHOR]

Background: Agrobacterium rhizogenes-mediated (ARM) transformation is a highly efficient technique for generating composite plants composed of transgenic roots and wild-type shoot, providing a powerful tool for studying root biology. The ARM transformation has been established in many plant species, including soybean. However, traditional transformation of soybean, transformation efficiency is low. Additionally, the hairy roots were induced in a medium, and then the generated composite plants were transplanted into another medium for growth. This two-step operation is not only time-consuming, but aggravates contamination risk in the study of plant-microbe interactions. Results: Here, we report a one-step ARM transformation method with higher transformation efficiency for generating composite soybean plants. Both the induction of hairy roots and continuous growth of the composite plants were conducted in a single growth medium. The primary root of a 7-day-old seedling was decapitated with a slanted cut, the residual hypocotyl (maintained 0.7-1 cm apical portion) was inoculated with A. rhizogenes harboring the gene construct of interest. Subsequently, the infected seedling was planted into a pot with wet sterile vermiculite. Almost 100% of the infected seedlings could produce transgenic positive roots 16 days post-inoculation in 7 tested genotypes. Importantly, the transgenic hairy roots in each composite plant are about three times more than those of the traditional ARM transformation, indicating that the one-step method is simpler in operation and higher efficiency in transformation. The reliability of the one-step method was verified by CRISPR/Cas9 system to knockout the soybean Rfg1, which restricts nodulation in Williams 82 (Nod-) by Sinorhizobium fredii USDA193. Furthermore, we applied this method to analyze the function of Arabidopsis YAO promoter in soybean. The activity of YAO promoter was detected in whole roots and stronger in the root tips. We also extended the protocol to tomato. Conclusions: We established a one-step ARM transformation method, which is more convenient in operation and higher efficiency (almost 100%) in transformation for generating composite soybean plants. This method has been validated in promoter functional analysis and rhizobia-legume interactions. We anticipate a broad application of this method to analyze root-related events in tomato and other plant species besides soybean. [ABSTRACT FROM AUTHOR]

This paper studies the finite-time state feedback stabilisation of stochastic high-order nonlinear feedforward systems. Based on the stochastic Lyapunov theorem on finite-time stability, by using the homogeneous domination method, the adding one power integrator and sign function method, constructing aLyapunov function and verifying the existence and uniqueness of solution, a continuous state feedback controller is designed to guarantee the closed-loop system finite-time stable in probability. [ABSTRACT FROM AUTHOR]

The work reports the theoretical investigation of the mechanism and regioselectivity of the Pd(OAc)-catalyzed hydrothiolation of heteroatom-substituted alkenes with benzenethiol leading to Markovnikov-type product. The reaction process includes: (1) activation of the S-H bond for benzenethiol by the catalyst Pd(OAc); (2) migratory insertion of the alkenes bearing heteroatoms into the Pd-S bond; (3) AcOH molecule attacks Pd-C bonds to give the product and release the catalyst. In addition, the computed results shown that Pd(OAc)-catalyzed hydrothiolation take place by two possible channels and get anti-Markovnikov-type or Markovnikov-type species. The Markovnikov-type reaction channel is more favored with the energy barriers of 21.9-25.6 versus 28.5-31.2 kcal/mol for the anti-Markovnikov-type pathway. The theoretical results and the experimental observations of Tamai and co-workers are consistent. This reaction would proceed in mild conditions and afford the Markovnikov-type products in high yields and regioselectivity. [ABSTRACT FROM AUTHOR]

This paper considers the global finite-time output feedback stabilization of a class of nonlinear highorder feedforward systems. By using the homogeneous domination method together with adding a power integrator method and overcoming several troublesome obstacles in the design and analysis, a global finitetime output feedback controller with reduced-order observer is recursively designed to globally finite-time stabilize nonlinear high-order feedforward systems. [ABSTRACT FROM AUTHOR]

In this paper, we study the global output feedback stabilisation of a class of high-order nonlinear systems with more general low-order and high-order nonlinearities. By constructing the novel Lyapunov function and observer, based on the homogeneous domination theory together with adding a power integrator method, an output feedback controller is developed to guarantee the equilibrium of the closed-loop system globally uniformly asymptotically stable. [ABSTRACT FROM PUBLISHER]

This paper considers the finite-time stabilisation for a class of high-order nonlinear systems with both low-order and high-order nonlinearities. Based on the finite-time Lyapunov stability theorem together with the methods of dynamic gain control and adding one power integrator, a state feedback controller with gains being tuned online by two dynamic equations is proposed to guarantee the global finite-time stabilisation of the closed-loop system. [ABSTRACT FROM PUBLISHER]

This paper investigates the global stabilization for a class of high-order time-delay nonlinear systems. Compared with the existing references, a distinct characteristic of this paper rests in time-delay entering high-order, low-order, and linear growth parts of system nonlinearities. Based on Lyapunov-Krasovskii theorem and necessary improvement of the adding a power integrator method, a continuous global state-feedback controller is constructed to preserve the equilibrium at the origin and guarantees the global asymptotic stability of the resulting closed-loop system. Finally, a simple example is provided to demonstrate the validness of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A theoretical investigation of the [3+2] cycloaddition reaction of the NHC-boryl azide with alkynes and nitriles has been presented by using the DFT (B3LYP) method. Solvent effects on these reactions have been explored by calculation that included a polarizable continuum model (PCM) for the solvent (CH). The title reaction could produce two different five-membered products (1,4-regioisomer and 1,5-regioisomer). The reaction pathway involves a one-step mechanism through a [3+2] addition where two nitrogen atoms of the N-heterocyclic carbene boryl azide adds to the C≡A (A=C or N) bond to form two new C-N or N-N bonds. For alkynes, the reactions can take place more easily to give 1,4-regioisomer product, while the reactions proceed for nitriles along the 1,5-regioisomer pathway. The reaction systems have high chemical reactivity with low barriers and could be favored. The calculations indicated that the cycloaddition reaction of alkynes and nitriles has the better regioselectivity. Our computational results are good consistent with the experimental observations of Merling and co-workers for [3+2]-dipolar cycloaddition reaction of N-heterocyclic carbene boryl azide. [ABSTRACT FROM AUTHOR]

This paper studies the state feedback control problem for a class of nonlinear systems with high-order and low-order nonlinearities. The introduction of the sign function together with the method of adding a power integrator and Lyapunov stability theorem makes the closed-loop system globally asymptotically stable. Exploiting the idea of how to deal with growth nonlinearities with both high order and low order being relaxed to some intervals is the focus of this work. [ABSTRACT FROM PUBLISHER]

The adsorption mechanism of a series of macroporous adsorption resins ( p-(CHNH)PhL (L = NH, OH, COOH)) with rutin have been investigated using density functional theory calculations at B3LYP/6-31G(d,p) level of theory. Solvent effects on these species were explored using calculations that included a polarizable continuum model for the aqueous solvent. In this article, the geometry structure, interaction energies and the infrared spectra for the stable reactants and the adsorption complexes were obtained and analyzed. The results show that the hydrogen-bonding have been formed in the adsorption complexes. The higher interaction energy is calculated for the carboxyl group, while the resin with amino group has the highest adsorption capacity for rutin. The adsorption complexes become more and more stable as increasing the number of adsorbents. Our theoretical study is in good explanation for the experimental results. [ABSTRACT FROM AUTHOR]

This paper studies the global stabilisation problem for a class of high-order nonlinear systems with multiple time delays. A distinct property of the systems to be investigated is that powers on the upper bound restrictions of nonlinearities are allowed to take values on a continuous interval. By introducing the sign functions and using the generalised method of adding a power integrator, this paper successfully designs a continuous global state-feedback controller independent of time delays. Moreover, a novel Lyapunov–Krasovskii functional is constructed to prove the globally asymptotic stability of the resulting closed-loop system. [ABSTRACT FROM PUBLISHER]

ABSTRACT To study the genetic characteristics and function of swine leukocyte antigen (SLA) class I from the Hebao pig, a rare inbreed in China, a pair of primers was designed to amplify the SLA-2 gene ( SLA-2-HB) and then the genetic characteristics of the gene were analyzed. The 3D homology modeling was used to analyze the structure and function of SLA-2-HB proteins. After cloning, sequencing and computer analysis, four SLA-2-HB alleles were found, all of 1119 bp. Sites 3-1097 were an open reading frame encoding 364 amino acids with two sets of intra-chain disulfide bonds comprising four cysteines situated in sites 125, 188, 227 and 283. By alignment of SLA-2-HB sequences with other SLA-2 alleles in the IPD database, 11 key variable amino acid sites were found in the extracellular domain of the SLA-2-HB alleles at sites 23(F), 24(I), 43(A), 44(K), 50(Q), 73(N), 95(I), 114(R), 155(G), 156(E) and 216(S), which could be used to differentiate other SLA-2 alleles. The 3D homology modeling demonstrated that the eight of 11 key variable amino acid sites were all in antigenic binding groove of SLA-2-HB proteins. The amino acid identities between SLA-2-HB and other SLA-2, SLA-1 and SLA-3 alleles were 86.2-97.0%, 85.0-93.9% and 83.3-88.6%, respectively. The phylogenetic tree of SLA-2-HB showed that it was relatively independent of the other SLA-2 genes. Furthermore, the SLA-2-HB alleles were similar to HLA-B15 and HLA-A2 functional domains and preserved some functional sites of HLA-A2. It was concluded that SLA-2-HB are novel alleles of SLA-2 and that the Hebao pig might have evolved independently in China. [ABSTRACT FROM AUTHOR]

The article focuses on a study conducted to analyze molecular characteristics of the SLA-1 gene from Chinese Hebao pigs. The SLA-1 gene from the Hebao pig was cloned and was then the molecular characteristics of the gene were analyzed. The results of the study showed that the Hebao pig is resistant to infectious diseases including classical swine fever (CSF) and suggests that key binding sites for antigen processing for SLA-1-HB might determine susceptibility to the infection.