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In this study, the enantiomer-specific bioactivity, bioaccumulation, and toxicity of fenpropathrin (FEN) enantiomers were investigated in soil-earthworm microcosms. The bioactivity order was

The authors of Li et al. 33:727–741 (2020) retracted this article because of figure composition errors. This article was retracted on 28 November 2022. In bacteria, FtsZ proteins form a Z ring that is the initial step preceding septal fission. FtsZ proteins enable the division of mitochondria in early eukaryotes and are present in some kingdoms but have been lost in animals, fungi, and plants. Here, we have identified two Phytophthora capsici ortholog genes of Escherichia coli FtsZs, designated PcFtsZ1 and PcFtsZ2. Overexpression of PcFtsZ2 in E. coli fully complemented the overexpression phenotype of EcFtsZ. In contrast, overexpression of PcFtsZ1 in E. coli had minimal impact on cell division and separation. Thus, we focused on evaluating the impact of altered expression of PcFtsZ2 in P. capsici, as it exhibited the strongest phenotype. PcFtsZ2 was expressed at the highest levels in mycelia, sporangia, and germinating cysts, as well as in late infection. PcFtsZ2 mis-expression lines showed aberrant asexual growth and development of P. capsici. Alterations in the expression of PcFtsZ2 changed the distribution of mitochondria in hyphae and sporangia and, also, affected the number, size, and shape of actin plaques. Silencing of PcFtsZ2 restrained growth and development of invasive structures, especially cysts and sporangia, substantially inhibiting the ability of transformants to cause blight lesions. In overexpressed transformant lines, cyst and sporangial germination rates were only half that of controls, but hyphal growth from direct germination of sporangia was more rapid than controls. These transformant lines were only slightly impaired in virulence relative to controls. This study emphasizes the essential role of the evolutionarily conserved FtsZ2 proteins in affecting cytoskeleton dynamics.

Metamorphosis relationship generation is a state-of-the-art practical applied testing method in the field of software testing industry, and its main idea is to detect whether there are errors caused by unsatisfied programs in two or more output results. The most important task is of course to generate the metamorphosis relationship, and such process is a kind of supervised learning with huge amount of calculation. As metamorphosis relationship generation is a kind of supervised learning whose specific loss function is based on absolute value and has poor derivability, it not only depends on huge amount of calculation, but also requires complex algorithms to get the optimal solution, as the traditional gradient descent (GD) method cannot work well in solving its loss function. In this paper, two improvements for metamorphosis relationship generation has been made: firstly, Huber loss function is introduced to make the main loss function derivable; secondly, fixed memory step gradient descent method with noise is introduced to solve the sawtooth effect and falling into local optimum problems. Via numerical analysis, it has been verified that the improved metamorphosis relationship generation has better performance.

The widespread use of quinolones in humans and animals has become a major threat to public health. In this study, a simple, rapid, sensitive, and high throughput method based on automatic solid-phase extraction and isotope dilution ultra-performance liquid chromatography tandem mass spectrometry was described for the determination of trace quinolones in environmental water. The proposed automated solid-phase extraction method was initially optimized, and the optimum experimental conditions found were 1 L water sample with 0.5 g/L Na

Pesticide pollution has gradually caused land degradation. In order to avoid this problem, it is recommended to use enantiomeric pesticides that have less impact on the soil. The degradation of CYF enantiomers and the effect on soil functions are closely related to microorganisms. (+)-CYF enantiomer is degradable preferred and further discovered that related microorganism that degrades enantiomers. CYF enantiomers alter the bacteria structure and decreased the bacteria abundance. The combination of high-throughput and quantitative PCR results showed that the diversity of the (+)-CYF treatment was significantly lower than that of the (-)-CYF (-30.41 to 44.60) treatment and the (+)-CYF treatment (-27.80 to 56.70%) was more capable of causing the decrease in the number of soil microorganisms. In addition, (+)-CYF severely interferes with nitrogen cycling-related functions. Furthermore, the soil microbial structure was changed to its original level by enantiomers posed. In the study of nitrogen cycle function, we found that both enantiomers can restrain the abundance of nitrogen cycle-related genes, especially the (+)-CYF treatment decreased more. CCA showed that g-Massilia and g-Arthrobacter are closely related to nitrogen fixation genes and nitrification genes and degradation of the two enantiomers of CYF by g-Arthrobacter is closely related. The biological effects of cyflumetofen enantiomers remain unclear. Bioassay results show that enantiomers have similar virulence to Tetranychus cinnabarinus. Therefore, while achieving the prevention and control effect, the use of a single isomer (+)-CYF has a higher potential risk to the soil ecosystem.

This paper investigated a novel hybrid precast pier system that utilized ultrahigh-performance concrete (UHPC). The pier combines features of emulative and nonemulative (of cast-in-place c...

Self-centering, precast, post-tensioned concrete, bridge columns can provide low-damage under earthquake loading and accelerated bridge construction. These columns can also be designed so that shear-slip occurs between precast segments to provide energy dissipation. This paper, first, presents experimental results of large-scale testing of pier specimens that can self-center and undergo shear-slip under cyclic lateral loading. In these tests, segment interface properties, which control shear-slip, changed as the silicone layer placed between each segment degraded during testing. Specimens with fresh silicone had more energy dissipation, lower stiffness, and higher residual displacements compared with the ones with degraded silicone. A hysteretic model is created to predict the global load-displacement behavior of piers under lateral loading by superimposing self-centering and shear-slip responses. Shear-slip measurements under both quasi-static and rapid cyclic tests were used to characterize the interface frictional properties to be used in hysteretic modeling. Friction coefficients of segment interfaces were also investigated under varying accumulative displacement, normal force, and shear-slip velocity. The proposed hysteretic model is validated using the experimental results. A parametric study was performed using the established hysteretic model to investigate the influence of friction properties of interface materials and initial post-tension forces on the seismic response. The results show that interface materials with lower friction coefficient will lead to enhanced energy dissipation, lower stiffness, and smaller self-centering capability. Selecting lower initial post-tension force decreases the stiffness. Finally, incorporating the hysteretic model in the Capacity-Demand-Diagram method, seismic response of piers with varying properties was predicted. The increase in friction coefficient and initial post-tension force consistently increases the maximum base shear demand. Increasing initial post-tension force decreases the peak displacement in most cases. Increasing friction coefficient can either increase or decrease the peak displacement.

This paper introduces a tessellated structural-architectural (TeSA) wall system concept with the potential for improving both resilience and sustainability of the built environment. Resili...

As is known to all, Generative Antagonism Network (GAN) plays an important role in the field of image generation and classification. However, there are some shortcomings in it, one of which is that the generator and discriminator cannot converge to the real data at the same time. Therefore, Triple-GAN is proposed. Compared with GAN, it is composed of three parts: classifier, generator and discriminator, which guarantees that the data distribution of generator and classifier can converge to the real distribution. Yet, there are still some traditional limitations in the field of activation function and gradient descent such as gradient disappearance and gradient explosion. Thus, this paper adopts the new activation function Mish, the gradient ascending method and the gradient descending method instead of the original activation function and the gradient ascending algorithm. When a certain sparsity prevents the gradient from exploding and disappearing, the smooth curve of negative input value near the origin makes up for the defect of inactivation of neurons flowing into large gradient,and thus achieving better activation efficiency and greatly improving the efficiency of deep learning.

Generative adversarial network is an important generation model in the fields of big data, machine learning and deep learning. For semi-supervised learning, the improved generative adversarial network plays an important role in image generation and classification. Triple-GAN is the best one among them, which consists of classifier generator and discriminator, and it guarantees that the data distribution of generator and classifier can converge to the real distribution. However, the activation function and the gradient descent method of the original generative adversarial network have not been changed, and still have traditional limitations, which are prone to gradient disappearance and gradient explosion. Therefore, this paper adopts the new activation function Xwish and the fractional gradient step descent method with fixed memory step gradient descent method instead of the original activation function and the gradient descent method. It makes up for the disadvantages of inactivation caused by neuron flowing into large gradient while preventing gradient explosion and gradient disappearance with certain sparsity and introduces adaptive parameters to achieve better activation efficiency, which greatly improves the efficiency of deep learning.

Uridine phosphorylase (UP) is a key enzyme of pyrimidine salvage pathways that enables the recycling of endogenous or exogenous-supplied pyrimidines and plays an important intracellular metabolic role. Here, we biochemically and structurally characterized two evolutionarily divergent uridine phosphorylases, PcUP1 and PcUP2 from the oomycete pathogen Phytophthora capsici. Our analysis of other oomycete genomes revealed that both uridine phosphorylases are present in Phytophthora and Pythium genomes, but only UP2 is seen in Saprolegnia spp. which are basal members of the oomycetes. Moreover, uridine phosphorylases are not found in obligate oomycete pathogens such as Hyaloperonospora arabidopsidis and Albugo spp. PcUP1 and PcUP2 are upregulated 300 and 500 fold respectively, within 90 min after infection of pepper leaves. The crystal structures of PcUP1 in ligand-free and in complex with uracil/ribose-1-phosphate, 2′-deoxyuridine/phosphate and thymidine/phosphate were analyzed. Crystal structure of this uridine phosphorylase showed strict conservation of key residues in the binding pocket. Structure analysis of PcUP1 with bound ligands, and site-directed mutagenesis of key residues provide additional support for the “push-pull” model of catalysis. Our study highlights the importance of pyrimidine salvage during the earliest stages of infection.

Mixed matrix membranes (MMMs) were fabricated by incorporating carboxylated multi-walled carbon nanotubes (MWCNTs) into a poly (arylene fluorene ether ketone) that contained amino groups (Am-PAFEK) matrix to improve CO2 separation performance. The combination of MWCNTs and Am-PAFEK exerted a favorable synergistic effect on the permeability and selectivity of membranes. The extraordinary smooth wall of MWCNTs acts as a highway through which gas passes, providing better permeability. The Am-PAFEK matrix itself has a dense internal structure that provides high gas selectivity. MWCNTs particles evenly distributed among the Am-PAFEK membrane due to the non-covalent bond interaction between the amino and carboxyl group. Efficient CO2 transport pathways were constructed by homogeneous dispersion of MWCNTs with in MMMs, leading to maintained good selectivity and enhanced permeability. When the amount of carbon nanotubes added was 3 wt.%, that increased by above 60% in comparison to the Am-PAFEK membrane permeability, the CO2/CH4 and CO2/N2 selectivity of the Am-PAFEK/MWCNTs-3% membrane achieved 35.02 and 30.09, respectively. Therefore, the strategy of blending MWCNTs with Am-PAFEK exhibited a promising approach for improving gas permeability.

Vaterite, the least stable phase among three anhydrous polymorphs of calcium carbonate (CaCO3), was prepared via the reaction between the ethanol solution of calcium chloride (CaCl2) and the aqueous solution of sodium carbonate (Na2CO3), which is named ethanol-calcium method. The effects of aging times and reaction temperatures on the formation of vaterite were investigated. The polymorphs and morphologies were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively, and Fourier transform infrared spectroscopy (FT-IR) was used to verify the existence of vaterite. XRD results indicate that the amount of vaterite decreases from 90.4% to 81.4% as increasing in aging times from 0 min to 42 h and decreases from 85.8% to 70.2% as increasing in reaction temperatures from 0 °C to 60 °C. SEM results show that vaterite and calcite as-prepared are their typical morphologies of spherical and rhombohedral, respectively. This research extends the route to prepare the metastable vaterite and provides new insights into its controllable synthesis.

This paper presents steady-state dynamic response analysis of recently developed two types of self-centering structural systems with viscous damping. One of them has nonlinear elastic behavior in the primary structures, and the seismic energy is dissipated by added viscous damping. The other system has elasto-plastic hysteretic behavior in the primary structures, and the seismic energy is dissipated by both yielding of primary structure and added viscous damping. While the developed self-centering structural systems have advantages in reducing residual displacement and acceleration, it is anticipated that such self-centering systems may have large displacement demand due to the potentially limited energy dissipation. The results obtained in this paper show that the supplemental viscous damping of 10% and 20% is required to effectively control the displacement demand for self-centering systems whose primary structural system is nonlinear elastic and elasto-plastic behaviors, respectively. The effects of various parameters of the hysteretic response on the system's seismic peak displacement demand were also investigated.

On May 5, 2019, a truck-tractor-trailer loaded with six coils of steel crashed into a pier column of the Dongguofenli Bridge located on the Yongjin Highway in Shengzhou, China, resulting in severe damage to the impacted pier column. Prior studies on heavy truck collision with bridge piers mainly based on finite element (FE) simulations. However, none of them examined the behavior of bridges under a real vehicle-bridge collision accident. To fill in this gap, this paper aims to reproduce the Dongguofenli Bridge vehicle collision accident and scrutinize the causes of the observed bridge damages. This is achieved by using the high-resolution simulation models for both the impacted bridge structures and the colliding heavy truck. The typical heavy truck model widely used in previous studies was employed and validated based on the experimental data. Four different methods were examined to reasonably capture the soil-pile interaction behavior during vehicle collisions. Important lessons were learned from the FE simulation that reproduced this accident: 1) the characteristics of the cargo (i.e., cargo type and cargo’s fixing method) play an important role in determining the response of the bridge and 2) the damage that occurred to the bridge pier is most likely attributed to the direct impact between the bridge and the cargo (steel coils) that slipped off the truck. The analysis results also revealed that using the state-of-practice method for defining the impact force may lead to an unconservative bridge design for vehicle impact resistance. The applicability of the bridge design provisions related to vehicle impact design was also examined and the code-prescribed vehicle collision load was found to be inadequate to produce the damages that are observed in either the high-resolution simulation results or the real collision accident.

In this work, we fabricated PIM-based mixed matrix membranes (MMMs) containing MOF-801/ionic liquid nanocomposites to enhance CO2 separation performance of pure polymer membranes. All membranes and MOF-801/ionic liquid nanocomposites were prepared by solution casting method and wet impregnation, respectively. The samples were analyzed by SEM, XRD, FTIR, TGA and Nitrogen adsorption-desorption measurements. The nanocomposites are composed of metal-organic framework (MOF) MOF-801 and ionic liquid (IL) adsorption capacity. MOF-801 can well control the dispersion of IL in the polymer matrix, which is conducive to exposing more active sites in the nanocomposites to improve the CO2 adsorption selectivity of MOF-801/ionic liquid nanocomposites. At the same time, the porous structure of nanocomposites also enhances the gas adsorption and diffusion, thereby improving the gas separation performance. Compared with pure PIM-1 membranes, the CO2 permeability and CO2/N2 selectivity of IL@MOF/PIM-5% MMMs was increased by 129% and 45% (CO2 = 9420 Barrer, CO2/N2 = 29）, respectively. Compared with MOF-801/PIM-1 MMMs, the permeability of CO2 decreased slightly but the selectivity of CO2/N2 increased from 27 to 29. The aging test showed that the CO2 permeability of MMMs could remain above 70% after 90 days. The anti-plasticization performance of MMMs has also been significantly improved. The CO2 separation performance of IL@MOF/PIM-5% MMMs significantly exceeded the 2008 Robeson upper bound, showing excellent gas separation performance and working stability.

Seismic fragility assessment using structural dynamic analysis remains challenging for complex systems due to the high computational demand, such as the sea-crossing cable-stayed bridges. The paper aims to overcome this difficulty by developing an efficient seismic fragility analysis framework based on endurance time method (ETM). To demonstrate the framework for developing fragility curves, an example sea-crossing cable-stayed bridge is used as a case study. The ETM framework is validated by comparing the calculated fragility curves with those calculated by IDA framework. It is shown that the ETM is capable of significantly reducing computational effort without compromising the accuracy of fragility analysis results. The validated framework is then used to discuss the seismic fragility of sea-crossing cable-stayed bridges under scour and earthquakes. The influence of the time duration of endurance time acceleration functions (ETAFs) on the structural fragility is discussed. The influence of the time duration of ETAFs on the component fragility varies across different components, but the system fragility increases with the increasing time duration on the whole. Scour can produce either beneficial or adverse effects on the component and system seismic fragilities depending on the scour depth.

Calcium carbonate (CaCO3) was successfully synthesized via the decomposition of calcium bicarbonate (Ca(HCO3)2) solution in the presence of polyethylene glycol with different molecular weights (PEG 6000 and PEG 10000). The semi-quantitative characterization by XRD indicates that calcite is the major phase and vaterite and aragonite are the minor phases at different reaction times. SEM images show that the rhombohedral particle is the dominant morphology, together with some rod-like particles, a few spherical particles and some hierarchical structures, such as snow-shaped particles and spherical particles assembled from slice-like particles. SEM and TEM morphological images reveal that the snow-shaped particle consists of three parts, i.e. the hexagon or spherical center, the trunk and the filling. TEM crystal lattice images and electron diffraction patterns indicate that the trunk is composed of large vaterite crystal(s), while the filling consists of small calcite crystals. Based on the above results, the formation mechanism of snow-shaped particles is also proposed in the present work.

Lincomycin A is a clinically important antibiotic produced by Streptomyces lincolnensis that is used against gram-positive bacteria. To increase the yield of lincomycin A, a calcium gluconate feeding strategy was studied in a 15 L bioreactor. The results showed that the addition time of calcium gluconate was optimal during the late fermentation process to ensure a higher yield of lincomycin A. The optimum addition was continuous feeding at a speed of 0.0638 g/L/h from 111 to 158 h, which can increase the lincomycin A titer to 9160 mg/L, 41.3% higher than that without gluconate feeding. Enzyme activities of the central metabolic pathways, accumulation of intermediate metabolites, NADPH and NADH concentrations, and NADPH/NADH ratio were determined to investigate the mechanism of enhanced lincomycin A production by calcium gluconate addition. The activities of key enzymes of the pentose phosphate pathway (PPP) (glucose 6-phosphate dehydrogenase) and TCA cycle (isocitrate dehydrogenase) were enhanced by approximately twofold. A higher ratio of NADPH/NADH was observed in the fermentation process with the optimized feeding strategy providing sufficient reducing power. These data indicated that more flux flows through the PPP and the TCA cycle to provide more precursors, ATP and reducing power to support the synthesis of lincomycin A. The results showed a new strategy to improve the production of lincomycin A by manipulating the flux through the PPP and the TCA cycle.

Ultrahigh-performance Concrete (UHPC) flexural members with high compression strengths need large amounts of steel confinement to meet the current code confinement requirements. This study investigated the impact of different steel confinement amounts on the flexural behavior of longitudinally reinforced UHPC beams. Four small beam specimens with different steel confinement reinforcement amounts and grades were tested under monotonic three-point loading until failure. Steel confinement reinforcement grades varied from Grade 60 to Grade 120. The confinement volumetric ratios of the four specimens were 50%, 110%, 30%, and 50% of the minimum requirement of ACI 318-14. All specimens were under-reinforced longitudinally. The specimen with the least amount of confinement failed due to excessive shear cracking. The other specimens failed under flexure in the form of longitudinal reinforcement fracture, and exhibited similar flexural strength and ductility levels regardless of the confinement amount. These results indicated the need for re-evaluating ACI 318-14 requirements on the confinement for UHPC flexural members, especially when the longitudinal reinforcement ratios are low. A numerical analysis based on section equilibrium was conducted and evaluated using the test results. The constitutive tensile model of UHPC was obtained through material tests. Several unconfined and confined concrete compression models in the literature were examined. Compared to the compression models developed for normal concrete, the existing models for fiber-reinforced high-strength concrete significantly improved the predictions of flexural moment strength and failure mode for UHPC.

Prolyl 4-hydroxylases (P4Hs) are members of the Fe2+ and 2-oxoglutarate- dependent oxygenases family, which play central roles in the collagen stabilization, hypoxia sensing, and translational regulation in eukaryotes. Thus far, nothing is known about the role of P4Hs in development and pathogenesis in oomycetes. Here we show that the Phytophthora capsici genome contains five putative prolyl 4-hydroxylases. In mycelia, all P4Hs were downregulated in response to hypoxia, but the expression of PcP4H1 was most affected. Strikingly, Pc4H1 was upregulated more than 110 fold at the onset of infection, and Pc4H5 was upregulated seven fold, while the expression of other P4H's were unchanged. Similar to well-characterized P4H proteins, the crystallographic structure of PcP4H1 contains a highly conserved double-stranded β-helix core fold and catalytic residues. However, the binding affinity of 2-oxoglutarate to PcP4H1 is very low. The extended C-terminal α-helix bundle and longer β2-β3 disordered substrate binding loop may help in confirming the peptide target of this enzyme.

A novel exposed column base (ECB) connection, featuring composite yield mechanism (i.e., a combination of anchor rod and base plate yielding), has been recently proposed in Japan for optimum seismic performance. This paper focused on investigating the effects of using composite yield mechanism on damage mitigation for ECB connections. In doing so, four two-thirds scale specimens, with different base connection configurations, were tested under combined flexure and axial load. Their performances were assessed and compared in terms of damage evolution, moment-rotation relationship and energy dissipation. The experimental results showed that for ECB connection with composite yield mechanism, both anchor rod and base plate will actively contribute to the moment resistance and energy dissipation. This can successfully postpone the interior anchor rod yielding and fracture, compared to the ECB connection with anchor rod yield mechanism. Meanwhile, the strain demands on exterior plate can be also released compared to the ECB connection with base plate yield mechanism. The relative contributions from anchor rod and base plate of ECB connection with composite yield mechanism can be controlled by changing the exterior plate thickness. In addition, an analytical method was proposed to predict the yield and ultimate moment strength for the Composite Yield ECB connection based on the principle of virtual work. The difference between predicted and measured moment strength is within 15%, showing the validity of the proposed method for moment strength prediction.

Bridges crossing navigable waterways have a high risk for vessel collision hazard, and are meanwhile experiencing significant ‘aging’ hazard due to the surrounding aggressive environments. These bridges must be designed to be resilient to both episodic (vessel collision) and chronic (structural deterioration) hazards. To achieve this goal, this paper will develop a novel fragility assessment framework for reinforced concrete (RC) bridges under vessel collision with the corrosion-induced structural deterioration being considered. The cornerstone of this fragility assessment framework is the computational model with the capability of accurately predicting vessel impact response and corrosion-induced deterioration measures. In doing so, detailed finite element (FE) modeling approaches, including reinforcement bond-slip effects, are firstly developed and validated by the experimental results. The effects of corrosion are characterized by a series of deterioration measures that can be implemented into FE models. These FE modeling approaches were utilized to model the baseline bridge. Three different exposure periods (i.e., 0, 50, and 100 years) and two types of vessel (barge and ship) are considered. Driven by the response data generated by the FE model, a surrogate model is developed to feature both accurate vessel-impact response estimates and negligible computation cost. This surrogate model is then employed to create fragility curves using Monte Carlo methods. Fragility analysis results have indicated the significant role played by corrosion in increasing the vulnerability of RC bridges under vessel collision throughout the lifetime of the baseline bridge. The probability of bridge collapse rises by almost 100% near the end of the bridge’s life. Significant differences were found for the damage evolution of the deteriorated bridge under barge impacts and ship impacts. Particular critical impact speeds were observed in the barge-impact response, but not during ship collisions.

This work mainly studies the CO2 separation performance of a new type mixed-matrix membranes (MMMs) based on MOF-801 as the microporous filler and PIM-1 as the polymer matrix. MMMs was successfully formed via simple casting/solvent evaporation approach at room temperature. The samples were systematically characterized by SEM, XRD, TGA and FTIR, the permeability-selectivity of MMMs to CO2, O2 and N2 was studied by gas permeability test. The experimental results show that the uniform dispersion of the CO2-philic MOF-801 filler provides a channel for the rapid and selective transport of CO2, so the MOF-801/PIM-1 MMMs revealed much higher CO2 permeability and CO2/N2 ideal selectivity (CO2 = 9686 Barrer, CO2/N2 = 27, all selectivity in the paper is ideal) than pure polymer membrane. After 90-days aging test, the CO2 permeability of MMMs remains above 70%, which reflects its good anti-aging performance. After 120 h continuous gas permeability test, it also shows good long-term working stability. The experimental results show that the good gas separation performance of MMMs exceeds the Robeson upper bound (2008), showing good application prospect for practical greenhouse gas CO2 separation.

PIM-1 and poly(arylene fluorene ether ketone) (Am-PAFEK) were synthesized by polycondensation. Their structures were characterized by 1H NMR and FT-IR spectral analyses. A series of flexible and transparent blend membranes were prepared by solution blending with different ratios of PIM-1 and Am-PAFEK. DSC and SEM analyses showed good compatibility between them. PIM-1 and Am-PAFEK in the blend membrane perform their respective functions. The former provides excellent permeability; the latter provides high selectivity for CO2. Addition of 20% Am-PAFEK into the blend membrane increased the gas separation selectivity of CO2/CH4 and CO2/N2 by 75% and 65%, respectively. The optimum separation performance was achieved with blend membrane with a CO2 permeability of 752.4 Barrer and a CO2/N2 selectivity ratio of 26.7, extremely close to the Robeson upper bound (2008). After 140-days aging test, the blend membranes still maintained above 70% CO2 permeability, indicating that it has good antiaging properties. Consequently, the new type of membranes have great potential in industrial applications.

RxLR genes are a prominent class of effectors in oomycetes, and almost half of these proteins contain a conserved sequence motif termed the WY domain, that may exist singly, or as divergent tandem repeats in different effectors. Here we describe the crystal structure of PcRxLR12 (63-488) from Phytophthora capsici at 3.0 A resolution. The structure consists of five tandemly arrayed WY-domains linked to each other by short connecting helices. Superposition of the WY-2 domain on the other four domains of PcRxLR12, show that the first α-helix termed the K motif, and Loop 3 which connects α3 and α4 are the key regions of structural divergence between the WY domains. A similar pattern was observed when WY-2 was superposed on the 11 WY domains from other oomycete effectors. We also note that an added connecting helix between WY domains in some RXLR effectors, ensures that the WY domains are oriented in the same direction.

Unbonded posttension strands are used between anchorages to provide restoring forces to self-centering structures. In this research, monotonic and quasi-static cyclic tests were performed o...

Cadmium (Cd) in coal, fly ash, slag, atmospheric deposition, soils and sediments collected from Tianjin, northern China, were measured to provide baseline information and determine possible Cd sources and potential risk. The concentrations of Cd in coal, fly ash and atmospheric deposition were much higher than the soil background values. Fallout from coal-fired thermal power plants, heating boilers and industrial furnaces has increased the Cd concentration in soils and sediments in Tianjin. The concentrations of Cd in soils of suburban areas were significantly higher than in rural areas, suggesting that coal burning in Tianjin may have an important impact on the local physical environment. Cd from coal combustion is readily mobilized in soils. It is soluble and can form aqueous complexes and permeate river sediments. The high proportion of mobile Cd affects the migration of Cd in soils and sediments, which may pose an environmental threat in Tianjin due to the exposure to Cd and Cd compounds via the food chain. This study may provide a window for understanding and tracing sources of Cd in the local environment and the risk associated with Cd bioaccessibility.