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Exploring the spatial distribution characteristics and variation law of soil pH and analyzing the impact of environmental factors on the spatial differentiation of soil pH are of great significance to the accurate management of soil pH and the sustainable utilization of soil resources in the complex mountainous environment of Anshun City. Based on 22 851 field sampling points, using the methods of global Moran's

Ultraviolet (UV)/chlorine draws increasing attention for the abatement of recalcitrant organic pollutants. Herein, it was found that TiO

Soil organic carbon (SOC) in agricultural land is influenced greatly by indeterminate human activity, making it difficult to understand the spatial pattern of SOC. Soil pH and topographic conditions are key indices in the Chinese Soil Genetic Classification System (CSGCS) and manage some critical factors that control the dynamics of SOC either directly or indirectly. To identify the extent to which pH and topographic factors control SOC levels in dry farming cropland soils of the mountainous region of Southwest China, we compared the differences along topographic gradients, and analysed the contribution of different factors in determining SOC status using analysis of variance (ANOVA) and linear regression. Our results indicated the SOC levels ranged from 10.46 g•kg− 1 to 37.60 g•kg− 1 and were significantly correlated with soil pH, landscape position, slope and elevation (p

Carbon stable isotope techniques were extensively employed to trace the dynamics of soil organic carbon (SOC) across a land-use change involving a shift to vegetation with different photosynthetic pathways. Based on the isotopic mass balance equation, relative contributions of new versus old SOC, and SOC turnover rate in corn fields were evaluated world-wide. However, most previous research had not analyzed corn debris left in the field, instead using an average corn plant δ 13C value or a measured value to calculate the proportion of corn-derived SOC, either of which could bias results. This paper carried out a detailed analysis of isotopic fractionation in corn plants and deduced the maximum possible bias of SOC dynamics study. The results show approximately 3‰ isotopic fractionation from top to bottom of the corn leaf. The 13C enrichment sequence in corn plant was tassel > stalk or cob > root > leaves. Individual parts accounting for the total dry mass of corn returned distinct values. Consequently, the average δ 13C value of corn does not represent the actual isotopic composition of corn debris. Furthermore, we deduced that the greater the fractionation in corn plant, the greater the possible bias. To alleviate bias of SOC dynamics study, we suggest two measures: analyze isotopic compositions and proportions of each part of the corn and determine which parts of the corn plant are left in the field and incorporated into SOC.

Cyanobacteria are the oldest oxygen-evolving photosynthetic organisms on the Earth. They are widely distributed in marine, freshwater, and terrestrial environments and contribute about 25% of global primary productivity. They are thought to be responsible for the conversion of the Earth’s atmosphere from anaerobic to aerobic about 2.4 billion years ago. This development permitted the evolution of aerobic bacteria, algae, plants, and animals. However, due to the emergence of oxidative environments on the Earth’s surface, soluble ferrous iron (Fe2+) was almost completely oxidized to hardly soluble ferric iron (Fe3+) in aquatic environments. The extremely low bioavailability of iron in the ocean has been considered as an important factor that is limiting global primary productivity. As photosynthetic organisms, cyanobacteria have higher iron demand than other non-photosynthetic organisms to meet the needs of photosynthetic electron transport and chlorophyll synthesis. The nitrogen-fixing cyanobacteria need even more iron to fix the inert dinitrogen gas. The contradiction between the high iron demand of cyanobacteria and their iron-limiting habitats has forced them to evolve special strategies to overcome iron deficiency during the long-period evolution. In this review, we summarized the recent perspectives on the physiological responses and special strategies of cyanobacteria to overcome the changing iron bioavailability in freshwater, coastal, and open-ocean environments.

To solve the problems of path planning and path tracking in the field of automatic driving, the path planning and tracking methods applicable to the actual environment under complex constraints are studied. Firstly, the improved double-tree RRT algorithm (RRT-Connect) based on bidirectional extended balance was introduced. Under the advantage of avoiding the modeling of space, the target preference function and the metric function were introduced in combination with the environmental constraints and the constraints of the vehicle itself. At the same time, combined with the regression detection and collision detection mechanism to solve the local minimum problems in motion planning, and greatly improve the effectiveness of path planning. Then generate a smooth continuous executable track based on the cubic spline interpolation function. Finally, the heading angle is obtained according to the vector field method and converted into a tangential angle to continuously track the path. The effectiveness, correctness and practicability of the algorithm are verified by simulation experiments.

Spray painting robots equipped with air spray guns have been widely used in the painting industry. In view of the low efficiency of single-nozzle air spray guns when spraying large targets, a new double-nozzle air spray gun structure was designed in this paper based on the Coanda effect of double jets. Firstly, a 3-D physical model of the double-nozzle air spray gun was built in Solidworks, in which unstructured grids were generated for the computational domain by ICEM. Secondly, the spray painting process was numerically modeled with the help of the computational fluid dynamics (CFD) software ANSYS-Fluent 16.0. The two-phase spray flow was calculated by coupling a discrete phase model (DPM) and the Taylor analogy breakup (TAB) method. The TAB model was applied to predict the secondary break-up. The DPM model was applied to predict the droplet trajectories. The geometry of an air spray gun has a significant influence on the spray flow field characteristics. The influence of the air spray gun geometry on the interference spray flow field characteristics and coating film thickness distribution were investigated by changing the values of the distance between the centers of the two paint holes (L) and the angle between the axes of the two paint holes (&theta, ). Numerical results show that the smaller L and &theta, are, the stronger the interference effect between the two jets, while the more concentrated the paint is in the central region of the target surface, the easier it is for overspray to occur. With increasing L and &theta, the interference effect gradually decreased and the extension distance of the coating film along the x-axis gradually increased. However, if L and &theta, are too large, the interference effect will become too weak and the shape of the coating film will become a concave, with more paint on both side regions and less paint in the central region, which will cause an uneven coating film. From the simulation results, it can be concluded that a more uniform coating film can be obtained when L = 30 mm and &theta, = 10&deg, The effective coating width of the double-nozzle air spray gun was increased by 85.7% compared with the single-nozzle air spray gun, which improved the spraying efficiency.

Corrosion mechanism of automotive mufflers was investigated by SEM (scanning electron microscope) and XRD (X-ray diffractomer) analysis. 409L and newly developed 439M steels were evaluated in terms of condensate corrosion tests for 5 periods, 10 periods and 20 periods separately. The relative lifetimes of 409L and 439M steels were predicted according to the extreme value analysis method and pitting corrosion models. Modelling studies demonstrated that the predicted relative lifetime of 439M ferrite stainless steel is 6. 8 times that of 409L steels. The extreme value analysis method was also successfully used in the road test. The estimated maximum corrosion depth of the 439M muffler is 0. 55 mm.

Xuzhou city lies on the north of Jiangsu province. Its geological conditions are complex, water resources are deficient and environment is vulnerable. At present, water pollution in Kui river area is very serious, the water movement and heat transfer characteristics of unsaturated zone in Kui river area was studied to provide a theory foundation for predicting pollution of unsaturated zone removing and transforming. The study was considered through the rule of energy flow and nutrient cycling under different vegetation cover: temperature of soil decreases with increasing depths in most area, but different vegetation cover causes vary between variation-rate in different temperature, which some vegetation cover cause temperature of soil increases with increasing depths.

Xuzhou city lies on the north of Jiangsu province, which geological conditions are complex, water resources are deficient and environment is vulnerable. At present, water pollution in Kui river area is very serious; Kui River nitrogen pollution had affected Coastal soil and chemical environment of groundwater. The monitoring sections are elected in the seriously polluted river, and downstream at the banks of river decorates with six monitoring sections. Each section from the river bank of 50m, 100m, 200m, 500m, 1000m, 1500m is arranged of monitoring points respectively, and each monitoring point is monitored for sampling test at different depths. The monitoring results of surface water showed that the content of ammonia-nitrite-nitrate was a decreasing trend along the flow direction. The nitrate nitrogen content would decrease further in December while the ammonium nitrogen content was on the rise, showing that the supplement of nitrogen pollution resources was still insufficient when the denitrification was stronger. The content of ammonium and nitrate nitrogen in soil was higher, and had some regular change features with the change of depth.

Distributed physically-based models have the predictive capacity to assess the effect of land use changes on groundwater dynamics across a range of scales. MIKESHE, which represents state-of-art of distributed hydrological model, is applied to the Skjern catchment. It is utilized to evaluate hydrologic impacts of land use changes in a watershed. Our overall objective was to quantitatively evaluate the effects of land use changes on watershed hydrology within the 1175 km2 Skjern catchment in Denmark. The results show that the soil is unsaturated and has bigger storage capacity. The groundwater recharge distribution has seasonal characters like the runoff, which mainly concentrated in winter and spring and decreased in summer and autumn.

The properties of soils derived from carbonate rock, red residua, and sand-shale in Guizhou province, China are essentially different. However, the effects of parent material and anthropogenic activities on the concentration of trace elements when the soils are converted into paddy soils are unknown. A total of 319 paddy topsoil samples (0–20 cm) were collected in a typical region to determine their relative contribution to the concentrations of trace elements in the soil. The results indicated that the contents of trace elements were far beyond the uncultivated soil background and the input of organic fertilizers was presumably responsible for accumulation of trace elements. In addition, principal component analysis showed that the first component included Cd, Cr, and As, which strongly associated with anthropogenic activities. Pb and Hg formed the second component, which related to both parent materials and anthropogenic input. Furthermore, the Cr and Hg contents in paddy soil derived from carbonate rock have higher values than other types of soils partly because of the high background values as well as slightly alkaline condition. In the paddy soil derived from red residua, high physical clay content accounted for enrichment of Pb.

The paper presents the magnetic field distribution from the armature winding currents in the slotted air gap of surface-mounted permanent magnet (SMPM) motors using the Schwarz- Christoffel(SC) mapping. With the method, a slotted structure of SMPM motors is transformed into a geometrically simpler domain. Compared with the result from the finite element method, the accuracy of the method is verified. The presented work can be a basic tool for optimizing design and performance analysis of permanent magnet motors.

This paper presents a novel method to reduce the inrush currents produced by interconnecting induction generators. The method is based on the sequential energization of the contactors and a grounding resistor connected at the neutral point of a wye-connected stator. Analytical developments are presented, which permit to determine the optimum value of the neutral resistor directly. Theoretical and simulation analysis show that the proposed method can be almost as effective as the traditional three series resistor method. The proposed method requires only one resistor and one bypass contactor and is therefore more cost-effective than the traditional methods.

For establishing rational farming mechanism, it is essential to know the relative contribution of different geological background and anthropogenic activities to trace elements in agricultural soil. In this paper, 282 surface soil samples were collected based on the different geological background. Five harmful trace elements (As, Cd, Cr, Hg and Pb) were analyzed. The results indicated most of trace elements contents were far beyond the threshold of uncultivated soil background, which indicate anthropogenic input strongly influenced on trace elements in agricultural soil. In addition, correlation analysis showed trace element contents exhibited high relationships with soil pH, C/N and physical clay (

There is considerable discussion and uncertainty in the literature regarding the importance of fresh litter versus older soil organic matter as sources of soil dissolved organic carbon (DOC) in forest floor. In this study, the differences of organic carbon concentration and stable isotope composition were analyzed under different background conditions to identify the origins of DOC in forest soil. The data show that there is no significant difference in SOC content between these collected soil samples (P > 0.05), but the litter-rich surface soils have relatively higher DOC concentration than the litter-lacking (P

To investigate the effect of occlusal reconstruction on blood flow velocity and cerebral oxygen saturation in patients with malocclusion.Thirty-three patients with malocclusion treated with occlusal reconstruction in Department of Stomatology, Medical School of Huzhou Normal College from Feb 2011 to Oct 2013 were enrolled in the study. The systolic peak flow velocity (vs), end-diastolic peak flow (vd) , mean peak flow velocity (vm) of middle cerebral artery and the oxygen saturation (rScO2) in the brain were detected at rest or chewing status by using transcranial Doppler color ultrasonography and near-infrared spectroscopy, respectively.In rest state, vm was significantly increased on 3 months after treatment, while vs and vd were significantly increased on 6 months after treatment and rScO2 were increased on 12 months after treatment (P0.05). In chewing state, vs, vm, and rScO2 were increased on 3 months after treatment, and vd was increased on 6 months after treatment (P0.05).Occlusal reconstruction can increase blood flow velocity of middle cerebral artery and cerebral oxygen saturation and improve oxygen supply of the brain in patients with malocclusion.

To construct human phage single-chain antibody (scFv) library against breast cancer, and to identify anti-HER2 specific antibodies from the human phage display scFv library to offer a stronger affinity sequence targeting HER2 for fusion protein targeting HER2 and CXCR4.Total RNA was extracted from the adjacent lymphatic tissue harvested from breast cancer patients. The variable regions of the whole antibody were amplified by using RT-PCR and were cloned into the vector pCANTAB-5E through a linker. The products were electroporated into competent E.coli TG1 cells. Recombinant phages specific for breast cancer cells were enriched in SKBR-3 after four rounds. The antigen-positive clones were selected by ELISA and immunohistochemistry.The fragment of VH and VL were about 375 and 330 bp and were linked in vitro to form scFv of 750 bp that was resistant to the breast cancer HER2 single strand. A fusion phage display library that contained total of 2.48×10(8) pfu /ml was established. ELISA and immunohistochemical results confirmed that the antibody has a strong affinity with HER2 antigen in breast cancer tissue. Compared to human IgG antibody, a scFv phage library against human breast cancer was successfully constructed with high capacity. The scFv was highly specific to HER2 antigen and the sequencing results indicated that VL and VH genes were highly homologous with the variable region of human antibody.This strategy may achieve new targeted antibody resistant to the breast cancer for clinical treatment and provide a carrier that uses HER2 as a target of the fusion protein for anti-tumor therapy.

The solubility of pyoluteorin (Plt) in water, dichloromethane, chloroform, and carbon tetrachloride was determined using an analytical method over the temperature range of (278.2 to 333.2) K. The solubility of Plt in chloroform is much higher than that in water, dichloromethane, and carbon tetrachloride. The solubility of Plt increases with increasing temperature in the four solvents, and all measurements were correlated with the Apelblat equation.

A pair of symmetrical furyl based ruthenium(II) complexes ([Ru(phen) 2 dpq-df] 2 + ( 1 ) and [Ru(bpy) 2 dpq-df] 2 + ( 2 ) (phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine, dpq-df = dipyrido (3,2-a:2′,3′-c) quinoxaline-difuran) have been prepared and characterized. The binding properties of both complexes toward G-quadruplex DNA have been investigated by fluorescence spectroscopy, UV–Vis spectroscopy, circular dichroism (CD), fluorescence resonance energy transfer (FRET) melting assays and molecular docking studies. The experimental results indicated that both Ru-complexes exhibited a remarkable “light switch” effect in the presence of hybrid G-quadruplex DNA. Interestingly, the “light switch” can be repeated off and on through the successive addition of Cu 2 + ions and EDTA, and all these behaviors can be observed even by the naked eyes. Moreover, FRET melting assay revealed that both complexes could be potential stabilizers for G-quadruplex architectures. The computational studies not only confirmed that the two complex molecules bound to one G-quadruplex DNA molecule, but also explained the “light switch” effect.

To determine the effects of parent material and land use on the concentration of trace elements in the agricultural topsoil of Guizhou Province, China, a total of 584 agricultural topsoil samples were collected in a typical region. The results indicate that the contents of trace elements (As, Cd, Cr, Hg, and Pb) in agricultural soils were greater than in the uncultivated soils, and the paddy fields exhibited higher contents of trace elements than dry lands. The enrichments of most trace elements in agricultural topsoil derived from carbonate rock were more serious. In paddy fields, Cd, Cr, and As showed positive relationships with soil organic matter (0.01) but were not affected by pH, carbon-to-nitrogen (C/N) ratio, and clay (0.05). Lead and Hg formed the second component in principal component analysis (PCA) and were closely related to pH and clay content. In dry lands, the trace elements were well correlated with pH, C/N, and clay (0.05). Analysis of PCA and correlation showed that Cd, Cr, and Hg were mainly derived from inorganic fertilizers, whereas Pb and As were primarily from organic manures. These results suggest that the effect of anthropogenic activities on paddy fields is more serious than on dry lands. Parent materials not only serve as sources of soil trace elements but also control the loss and accumulation of trace elements by affecting soil physicochemical properties, especially in dry lands.

Migration of a bullet to a distant part of the body after a gunshot is rarely observed in the clinical setting, and migration to the heart is even rarer. There are usually no clear symptoms or signs from migration of a bullet. The bullet can be easily missed and sometimes identified in a review examination. A case of bullet migration to the heart 2 months after a gunshot to the left knee was reported.

BACKGROUND: Pyoluteorin (Plt) is a polyketide metabolite produced by fluorescent Pseudomonas. It controls a wide range of pests, including bacteria, epiphytes and weeds. It could become widely used as a new biological pesticide. However, ignorance of the stability of Plt is an obstacle to its use. This work studied the stability of Plt and its degradation under different conditions, including temperature, pH and UV–visible light irradiation. RESULTS: Degradation of Plt followed first-order reaction kinetics. The degradation rate increased with increased temperature. The derived activation energy was 11.06 J mol−1 K−1. Plt was relatively stable in neutral solutions, in contrast to acid and alkaline solutions. Visible irradiation had no obvious effect on Plt stability, while UV irradiation greatly decreased its half-life to 3–4 days, in contrast to its half-life of 25 days in the dark. CONCLUSION: Plt is relatively stable in pure water solutions and at room temperature, with a half-life of more than 20 days. However, UV irradiation and acidic or alkaline solutions will enhance its degradation, reducing its half-life by a factor of 0.1–0.3. Before Plt is widely used as a pesticide, it might be necessary to modify the structure of Plt to make it more stable. Copyright © 2009 Society of Chemical Industry

A novel graphene(GN)/carbon black(CB) binary conductive additive has been developed, which is characterized by a unique microstructure and excellent performance for lithium ion batteries (LIBs). It was fabricated using a hydrothermal process, followed by heat treatment. The introduction of CB particles prevents GN from agglomerating and hence improves the electronic conductivity of the resulting additive. CB particles can also enhance the Li + ion diffusion, owing to a reduction of the GN fraction and an increase in electrolyte adsorption. Therefore, the rate performance of the LIB is improved to some extent. Experimental data shows that the specific capacity of LiFePO 4 containing 5 wt% of this binary conductive additive (after 900 °C treatment) is 73 mAh/g at 10 °C, which is superior to that of LiFePO 4 with 10 wt% of CB (62 mAh/g). Compared with the latter, the former has a specific capacity increase of 25% based on the mass of the whole electrode and shows superior cycle stability. [New Carbon Materials 2015, 30(2): 128–132]

Amino acids Tyr14 and Arg22 in trichosanthin are residues on helix A1 close to the active-site cleft. They are invariant in various type-I and type-II ribosome-inactivating proteins. In this study, Tyr14 was changed to Phe and Arg22 to Lys and Leu. Modified proteins were purified, and activities compared by assaying their median inhibitory concentration (ID50) on a rabbit-reticulocyte-lysate protein-synthesis system. While the ID50 of wild-type trichosanthin was 0.02 nM, those for [Phe14], [Lys22], [Leu22] and [Phe14, Leu22]trichosanthin were 0.10, 0.03, 0.25 and 0.15 nM, respectively. Therefore, compared with Tyr14, Arg22 appears to play a more important role in trichosanthin. Structural studies on [Leu22]tricho-santhin showed that two water molecules occupy the space left by the side chain of Arg22, and hydrogen bonds exist between these water molecules and nearby residues to retain the conformation. The use of intermolecular rather than intramolecular hydrogen bonds may have an adverse effect on stability or folding of the protein and results in a mild decrease in activity.