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When the sinusoidal buckling of suspended tubular strings is transforming to helical buckling, the deformation changes drastically, which makes the tubular strings extremely unstable. The quantitative description of this buckling configuration in previous theoretical studies is not precise enough. In our current study, dynamic relaxation method is applied to carry out numerical simulation of buckling transition of suspended tubular strings. To obtain stable buckling configurations, larger Rayleigh damping is used to attenuate the dynamic effect. With the increase of axial compression load, the lateral buckling of the suspended strings suddenly becomes spiral shape with two contact points. As the string length increases, the position of the lower contact point remains almost at the same position. While the upper contact point gradually moves upward, and the helix angle between the two points increases and gradually tends to be constant. The maximum contact force is located at the lower contact point, the maximum shear force is located at the bottom of the strings, and the dimensionless distance between the location of the maximum bending moment and the well bottom is about 1.0. These loads, including the maximum contact force, maximum shear force and maximum bending moment, gradually decrease with the increasing string length and tend to be constant. The dimensionless critical load is reduced from 4.41 to 3.81 with the effect of string length. The critical load calculated in this paper is the minimum value when helical buckling just occurs. The results obtained in the current study have wide engineering applications, particularly in failure analysis and prevention of helical buckling.

As emerging sensory ensembles, Ag(I)-thiolate coordination polymers have been drawing great research interests in the past few years. Ag(I)-thiolate coordination polymers feature unique physical properties such as semiconductivity, luminescence, photothermal and thermochromic effects, which could be leveraged to build physical and chemical sensors, as well as novel multifunctional biomaterials. This review summarizes the synthesis, structures and applications of Ag(I)-thiolate coordination polymers as sensory ensembles towards physical parameters such as temperature and light and chemical analytes including ions, VOCs, amino acids and saccharides. Developments of functional hydrogels for chemosensing and in situ drug delivery are also discussed.

Reported here is the induced helical aggregation of an achiral cationic perylene-3,4-dicarboximide (1) that contains a phenylboronic acid group, together with UMP that bears a cis-diol moiety able to interact with boronic acid and an imide group known to coordinate with Hg2+. In selected solvents, 1 exists in monomer form, even in the presence of either UMP or Hg2+. Helical aggregation only takes place if 1 is mixed with both UMP and Hg2+, which is shown to result from the formation of a building block consisting of five components in the form 1–U–Hg2+–U–1. Strong exciton-coupled circular dichroism signals were observed in the absorption window of the achiral dye chromophore, demonstrating the transfer of the chirality of UMP to the supramolecular aggregates of P-helicity. Synergism was shown to occur upon aggregation of the 1–U–Hg2+–U–1 building block, as substantially enhanced affinity and binding selectivity were observed for UMP and Hg2+, despite the otherwise weak and less selective interactions of 1–UMP and UMP–Hg2+. In support of this synergism, the g-factor of the aggregates was found to be 1.4×10−2, which represents a high value. We thus show a strategy of in situ construction of a building block from multiple components, among which the interactions can be weak and less selective. Therefore, the design and syntheses of the constituent components are substantially simplified, yet diverse functions can be expected from their supramolecular aggregates.

As a new emerging area in chemical sensing, sensing using supramolecular aggregates exhibits unique advantages over that using conventional small-molecule chemical sensors, in terms of high sensitivity and selectivity, and the simplicity of the sensory building blocks. This Feature Article outlines the recent research progress made in sensing based on induced supramolecular aggregation-disaggregation. The reviewed sensory building blocks, in general, in the form of a small molecular sensor, yet with a much simpler structure, which form aggregates, are those of perylene derivatives, pyrene derivatives, tetraphenylethylene derivatives, metallophilic species and metal-organic frameworks.

Although a linear relationship between the optical activity (normally the CD signal) and the enantiomeric excess (ee) of chiral auxiliaries has been the most commonly observed dependence in dynamic supramolecular helical aggregates, positive nonlinear CD-ee dependence, known as the "majority-rules effect" (MRE), indicative of chiral amplification, has also been well documented and to some extent understood. In sharp contrast, the negative nonlinear CD-ee dependence has been much less reported and is not well understood. Here, the state of the art of both the positive and negative nonlinear CD-ee dependence in noncovalently bound supramolecular helical aggregates is summarized, with the hope that the vast examples of supramolecular aggregates showing positive nonlinear dependence, in terms of the methods of investigations, variations in the structure of the building block (single species or multiple species), and theoretical modeling using the mismatch penalty energy and helix reversal penalty energy, would help to guide the design of building blocks to form aggregates showing negative nonlinear dependence, and thus to understand the mechanisms. The potential applications of those functional supramolecular aggregates are also discussed.

To improve the atmospheric environment of coastal areas, it is important to coordinate the accomplishment of the Emission Control Areas (ECAs) program development. However, it is difficult to achieve this objective to align the conflict interest between the government and shipping companies. This paper analyzes the differences in the benefits of the two main subjects in the implementation of China's ECA supervision. Then, based on a non-perfect rational hypothesis, this paper constructs an evolutionary game model to analyze and test the dynamic changes of participants' decision-making. Furthermore, we contrast the effects of the interfering elements (e.g., uncooperative penalty, external benefits, the shipping company cost, and third-party report rate) on their decisions under various terms, by applying simulation analysis method. The paper's outcomes demonstrate that, to inspire shipping companies to comply with ECA regulations, the government should apply a strategy, which is following dynamic penalty, to make shipping companies more willing to execute the ECA regulation within less time. Additionally, enhancing the external benefits of cooperative shipping companies and encouraging the participation of third-parties including non-governmental organizations and individuals in monitoring ECAs, are effective ways of stimulating shipping companies to comply with ECA regulations.

Dose-response (toxicity) relationships explain how the response changes with exposure doses. However, the results of tests or observations are commonly based on total concentrations of contaminants in environments, not the exposure dose that causes toxicity. In the present study, the copper (Cu) phytotoxicity to barley root elongation was studied in 17 representative Chinese soils. Also, the EDTA-extractable Cu concentration was used to evaluate the extractability of Cu in soils. The results showed that the concentrations of EDTA-extractable Cu accounted for 89.6-91.2 % of total added Cu in soils and that soil pH, organic carbon content (OC) and cation exchange capacity (CEC) could explain over 85 % of the variance in Cu phytotoxicity thresholds based on EDTA-extractable concentration. The integrated relationship of EDTA-extractable Cu doses, toxicity, and soil properties was firstly derived quantitatively. The EDTA-extractable Cu plus soil properties can explain more than 90 % of the variance in the toxicity response of barley root elongation. The new integrated model based on dose-toxicity-soil properties will provide an approach for risk assessment of contaminated soils with different Cu sources to avoid the overestimation of the risk based on total Cu concentrations in soils, and to develop a reasonable remediation strategy for Cu contaminated soils.

To reveal the variation tendency of melting temperature Tm, melting entropy Sm and melting enthalpy Hm in nanoscale and the physical origin is of benefit for the understanding of the melting behavior of nanoparticles (NPs), which is critical for the design of nanodevices. In this work, a simple thermodynamic model without any adjustable parameters is proposed to predict the size dependence of Tm(D), Sm(D) and Hm(D) of metallic NPs where D denotes size. The results show that Tm(D), Sm(D) and Hm(D) functions all drop with decreasing size. The size dependence of these functions is predominated by the ratio of solid-liquid interface energy γsl and solid-liquid interface stress fsl or γsl/fsl. We find that γsl(D) exhibit much more reduction than fsl(D) when D decreases, and the difference in the size dependence of γsl(D) and fsl(D) on D is the origin of abrupt decrease of Tm(D) when D below 10 nm. The good agreement between the model prediction and the available experimental data and the results of molecular dynamics simulations, as well as other theoretical models confirms the validity of this work.

Powdery mildew (Blumeria graminis) and stripe rust (Puccinia striiformis f. sp. Tritici) are two of the most prevalent and serious winter wheat diseases in the field, which caused heavy yield loss of winter wheat all over the world. It is necessary to quantitatively identify different diseases for spraying specific fungicides. This study examined the potential of quantitative distinction of powdery mildew and yellow rust by using hyperspectral data with continuous wavelet transform at canopy level. Spectral normalization was processing prior to other data analysis, given the differences of the groups in cultivars and soil environment. Then, continuous wavelet features were extracted from normalized spectral bands using continuous wavelet transform. Correlation analysis and independent t-test were used conjunctively to obtain sensitive spectral bands and continuous wavelet features of 350～1 300 nm, and then, principal component analysis was done to eliminate the redundancy of the spectral features. After that, Fisher linear discriminant models of powdery mildew, stripe rust and normal sample were built based on the principal components of SBs, WFs, and the combination of SBsWFs, respectively. Finally, the methods of leave-one-out and 55 samples which have no share in model building were used to validate the models. The accuracies of classification were analyzed, it was indicated that the overall accuracies with 92.7% and 90.4% of the models based on WFs, were superior to those of SFs with 65.5% and 61.5%; However, the classification accuracies of Fisher 80-55 were higher but no different than leave-one-out cross validation model, which was possibly related to randomness of training samples selection. The overall accuracies with 94.6% and 91.1% of the models based on SBsWFs were the highest; The producer’ accuracies of powdery mildew and healthy samples based on SBsWFs were improved more than 10% than those of WFs in Fisher 80-55. Focusing on the discriminant accuracy of different disease, yellow rust can be discriminated in the model based on both WFs and SBsWFs with higher accuracy; the user’ accuracy and producer’ accuracy were all up to 100%. The results show great potential of continuous wavelet features in discriminating different disease stresses, and provide theoretical basis for crop disease identification in wide range using remote sensing image.

The uncertainty in the risk assessment of trace metal elements in soils when total metal contents are used can be decreased by assessing their availability and/or extractability when the soils have a high background value or different sources of trace metal elements. In this study, the added water-soluble nickel (Ni) toxicity to barley root elongation was studied in 17 representative Chinese soil samples with and without artificial rainwater leaching. The extractability of added Ni in soils was estimated by three sequential extractions with ethylenediaminetetraacetic acid (EDTA). The results showed that the effective concentration of EDTA extractable Ni (EC50), which caused 50% inhibition of barley root elongation, ranged from 46 to 1019 mg/kg in unleached soils and 24 to 1563 mg/kg in leached soils. Regression models for EDTA extractable Ni and total Ni added to soils against soil properties indicated that EDTA extractable Ni was significantly correlated with the total Ni added to soils and that pH was the most important control factor. Regression models for toxicity thresholds based on EDTA extractable Ni against soil properties showed that soil citrate dithionate extractable Fe was more important than soil pH in predicting Ni toxicity. These results can be used to accurately assess the risk of contaminated soils with high background values and/or different Ni sources.

Based on the panel data of 14 major ports in China from 2003 to 2014, this paper evaluates the investment efficiency of Chinese ports and its influencing factors. Considering that the ports’ input and output indicators are difficult to measure with a definite function, the Data Envelopment Analysis (DEA) is applied to evaluate the investment efficiency of 14 major ports in China. Then the panel data model is applied to analyze the influencing factors of port investment efficiency. The study find that from 2003 to 2014 with the competition among ports, the investment efficiency of the ports in China is decreasing. Due to the different influence of each factor, the investment efficiency of the port is unbalanced in temporal and spatial distribution, there is large differences between regions. The main factors of ports investment efficiency is the level of economic development of the hinterland, but the emergence of a new mode of economic growth will lead to lowering investment efficiency of the port.

Size, dimensionality and pressure play important roles on modulating band gap (Eg) of semiconductor nanocrystals, and have attracted extensive attention in recent years. In this letter, a simple thermodynamic model is developed and the competition relation among size, dimensionality and pressure effects on Eg is discussed. The accuracy of our prediction is confirmed by the experimental data and simulation results of CdSe and ZnO nanocrystals. This model provides a new insight into the size, dimensionality and pressure effects on Eg and guides the optimal selection as design quantum devices.

Remarkable enhancements in tensile strength (∼625 MPa) and elongation ratio (∼1%), being three and five times, respectively, as large as those of the binary Fe 81 Ga 19 alloy, were obtained in situ dual-reinforcement (TaC particle +TaC dendrite )/Fe 81 Ga 19 magnetostrictive composites due to grain refinement and secondary-phase reinforcement.

The ownership structure which has a huge impact on company operation performance is the foundation of corporate governance structure choice. At present, the number of China's listed port companies is the largest in the world; however, they have a very complex ownership structure. This study discusses the impact of ownership structure on the operation performance of the Chinese ports. This empirical research applies factor analysis to evaluate the operation performance of listed port companies, and then adopts linear regression analysis based on the evaluation results to explore the impact of ownership structure to operation performance. Finally, it proposes recommendations for optimizing the ownership structure of listed port companies, in order to promote a better and faster development of China's port industry. The empirical results show that for most of the listed port companies, the largest shareholder is in the absolute controlling position, and the gap between the largest shareholder and the second largest shareholder is very large, which means the ownership concentration is relatively high. Meanwhile, the top five shareholders equity ratio squared is in negative correlation with operation performance.

The frequency-space (f-x) empirical mode decomposition (EMD) denoising method has two limitations when applied to nonstationary seismic data. First, subtracting the first intrinsic mode function (IMF) results in signal damage and limited denoising. Second, decomposing the real and imaginary parts of complex data may lead to inconsistent decomposition numbers. Thus, we propose a new method named f-x spatial projection-based complex empirical mode decomposition (CEMD) prediction filtering. The proposed approach directly decomposes complex seismic data into a series of complex IMFs (CIMFs) using the spatial projection-based CEMD algorithm and then applies f-x predictive filtering to the stationary CIMFs to improve the signal-to-noise ratio. Synthetic and real data examples were used to demonstrate the performance of the new method in random noise attenuation and seismic signal preservation.

We report a dynamic covalent approach to transmembrane transport of amino acids by the formation of a three-component assembly. A mixture of a squaramide and a lipophilic and electrophilic aldehyde is shown to synergistically transport highly polar glycine (Gly) across vesicle membranes. The transport was investigated by a 13C NMR assay, an osmotic response assay and a newly-developed fluorescence assay suitable for measuring Gly influx, and other fluorescence assays for leakage and pH change. The transport is proposed to occur via a hydrogen-bonded anionic glycine hemiaminal/imine, accompanied by transport of OH- in the opposite direction. Several control experiments support the role of hemiaminal/imine in the observed facilitated Gly transport. Proton NMR studies of a biphasic system show the presence of both the hemiaminal and imine formed between Gly and an aldehyde. Interestingly, the synergistic effect has also been observed for sarcosine (Sar) that can form hemiaminals but not imines. The results demonstrate the potential of hemiaminal formation for the facilitated transport of substrates containing primary and secondary amino groups.

A near infrared probe for sensitive colorimetric and fluorimetric detection of nerve agent mimics, DCP and DCNP, was reported based on the activation of a carboxylic acid group by the mimics to conduct an intramolecular amidation reaction in the heptamethine chromophore, where its absorption or excitation maximum wavelength could be greatly red-shifted by attenuating the electron-donating ability of the amine group in the bridgehead site of heptamethine cyanine.

A biocompatible fluoride receptor has been developed where the interaction between the boronic acid ester and amine (NH) results in fluoride ion selectivity and enhanced fluorescence quenching.

A mixture of two simple perylene-containing receptors was found to bind bifunctional L-DOPA synergistically and tightly via orthogonal boronate ester and imine bond formation in neutral aqueous solutions, the resulting three-component assembly forming optically active long fibrous aggregates.

In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment (WEEE). The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In addition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain for WEEE.

The phytotoxicity of added copper (Cu) and nickel (Ni) is influenced by soil properties and field aging. However, the differences in the chemical behavior between Cu and Ni are still unclear. Therefore, this study was conducted to investigate the extractability of added Cu and Ni in 6-year field experiments, as well as the link with their phytotoxicity. The results showed that the extractability of added Cu decreased by 6.63% (5.10%–7.90%), 22.5% (20.6%–23.9%), and 6.87% (0%–17.9%) on average for acidic, neutral, and alkaline soil from 1 to 6 years, although the phytotoxicity of added Cu and Ni did not change significantly from 1 to 6 years in the long term field experiment. Because of dissolution of Cu, when the pH decreased below 7.0, the extractability of Cu in alkaline soil by EDTA at pH 4.0 could not reflect the effects of aging. For Ni, the extractability decreased by 18.1% (10.1%–33.0%), 63.0% (59.2%–68.8%), and 22.0% (12.4%–31.8%) from 1 to 6 years in acidic, neutral, and alkaline soils, respectively, indicating the effects of aging on Ni were greater than on Cu. The sum of ten sequential extractions of Cu and Ni showed that added Cu was more extractable than Ni in neutral and alkaline soil, but similar in acidic soil.

Toxoplasma gondii has a complex life cycle and pathogenic mechanisms. Acute T. gondii infections in mice often result in death, whereas in chronic infections, the parasites may persist in the host tissues as intraneuronal or intramuscular cysts. However, the virulence of T. gondii strains in mice varies with its genetic background. The present study investigated the pathogenicity and pathological lesions of two T. gondii isolates from China: namely, TgCatCHn2 (ToxoDB#17) and TgCatCHn4 (ToxoDB#9). The virulent (ToxoDB#216) and avirulent (VEG) strains were employed as controls. Toxoplasmosis was induced by inoculating BALB/c mice with oocysts of the strains of T. gondii VEG, ToxoDB#216, TgCatCHn2 (ToxoDB#17), and TgCatCHn4 (ToxoDB#9), respectively. As a result, one oocyst of ToxoDB#216 could kill a mouse within 10 days post inoculation (DPI). The survival time of the mice for T. gondii TgCatCHn2 and TgCatCHn4 was >60 DPI for 106/mL oocysts, but this concentration (106/mL oocysts) of VEG strain could kill mice within 11 DPI. Compared with the strains of T. gondii ToxoDB#216 and VEG, the lesions in the small intestines of the strains of TgCatCHn2- and TgCatCHn4-infected mice were significantly smaller (P 0.05). However, the granules in the PCs showed negative lysozyme expression in the intestines of mice infected with T. gondii TgCatCHn2 and TgCatCHn4. Thus, T. gondii strains of TgCatCHn2 (ToxoDB#17) and TgCatCHn4 (ToxoDB#9) were avirulent strains, they triggered an inhibition of lysozyme expression in the granules of PCs of the mouse intestine. These effects may in turn lead to intestinal dysbiosis, which may be related to further parasitic invasion of the intestines. The findings of the present study further expand the spectrum of the pathogenic features of various Chinese isolates of T. gondii.

We report a strategy for enhanced performance of fluorescent sensing of biologically relevant species that often bind with natural receptors via multiple interactions. We propose making a fluorescent sensory molecule to form H-aggregates such that its emission is quenched leaving a low background, and upon binding to a biologically relevant species, the aggregate switches to another form in which the fluorescent species is better protected to afford a stronger emission signal. Meanwhile, the aggregated fluorescent dyes afford multiple interactions with the sensing species that require multiple binding sites. The lower background, stronger binding, and stronger signal would therefore lead to a much higher sensing performance, as improved selectivity would also result in along with the signal amplification. We thus designed a near-IR cyanine dye bearing two boronic acid groups (Cy-BA) for fluorescent sensing of ATP such that the boronic acid groups in the dye molecule bind to the cis-diol moiety in ATP. Introduction of the cationic surfactant dodecyltrimethylammonium bromide (DTAB) below its critical aggregation concentration is key because Cy-BA molecules made into H-aggregates were practically nonfluorescent. Upon mixing with ATP, a dramatic enhancement in the fluorescence occurred because of the formation of ATP/Cy-BA/DTAB vesicles in which the fluorescent dye is well dispersed and protected. This sensing scheme, despite the dynamic nature of the boronic acid/cis-diol interaction, weakness of the electrostatic interactions among ATP/Cy-BA/DTAB, and poor selectivity of these interactions, allows for highly sensitive and selective detection of ATP in aqueous solution.

Recently, various convolutional neural network (CNN) models have demonstrated their powerful ability as a universal representation for different image recognition tasks. In this paper, image retrieval with different kinds of CNN is considered. Firstly, we extract three kinds of CNN features with the current popular pre-trained CNN models to process image retrieval, respectively. Then, we compute weighted average of the similarity scores of these CNN features and propose an image retrieval algorithm based on the fused CNN features. Extensive experiments on two publicly available datasets well demonstrate that the proposed algorithm is clearly better than the retrieval algorithms based on individual CNN features and other current image retrieval algorithms.

The felids are the only definitive hosts of Toxoplasma gondii, which could excrete oocysts into the environment and provide an infection source for toxoplasmosis in various warm-blooded animal species, particularly the captive felids that live close to human communities. The infection rate of the captive felids is a perfect standard in detecting the presence of Toxoplasma gondii oocysts in the environment. In this study, sera or tissue samples from zoo (1 young tiger, 2 adult tigers, 6 young lions), farm (10 masked palm civets), and pet hospital (28 cats) from Henan Province (China) were collected. The sera (n = 47) were tested for immunoglobulin G (IgG) antibodies against T. gondii by using modified agglutination test (MAT), whereas the hearts tissue (n = 40) were bioassayed in mice to isolate T. gondii strains. The genotype was distinguished by using PCR-RFLP of 10 loci (SAG1, SAG2, SAG3, GRA6, BTUB, L358, c22-8, PK1, c29-2, and Apico). The detection rate for the T. gondii antibody in captive felids was 21.3% (10/47). One viable T. gondii strain (TgCatCHn4) was obtained from a cat heart tissue, and its genotype was ToxoDB#9. The oocysts of ToxoDB#9 were collected from a T. gondii-free cat. The virulence of TgCatCHn4 was low and no cysts were detected in the brain of mice at 60 days post-inoculation. The finding of the present study suggested a widespread exposure of T. gondii for felids in Henan Province of central China, particularly those from the zoological gardens and homes. ToxoDB#9 was the predominant strain in China. Preventive measures against T. gondii oocyst contamination of various components of the environment should thus be implemented, including providing pre-frozen meat, well-cooked cat food, cleaned fruits and vegetables, monitoring birds and rodents, inactive T. gondii oocysts in felids feces, and proper hygiene.

We report the first example of C–I···π halogen bonding driven supramolecular helix in highly dilute solution of micromolar concentration, using alanine based bilateral I-substituted N-amidothioureas that contain helical fragments, the β-turn structures. The halogen bonding interactions afford head-to-tail linkages that help to propagate the helicity of the helical fragments. In support of this action of the halogen bonding, chiral amplification was observed in the supramolecular helix formed in acetonitrile solution. The present finding provides alternative tools in the design of self-assembling macromolecules.

Along with the drastic competition among ports, the strive for the vast economic hinterland and the supply of goods have become strategic problems for port operators. At the same time, port enterprises are paying more and more attention to the construction of dry ports. This article establishes the port cooperation performance evaluation index based on the balanced score card method and uses the grey relational degree method to evaluate the cooperation performance between seaports and dry ports. Finally using Qingdao port and Xi'an port as an example, and Zhengzhou port and Lanzhou port as benchmarks, the application of this evaluation method is introduced in detail. The conclusion reveals that cooperation between Qingdao port and Xi'an port has deficiencies in customer satisfaction, financial cooperation and non-market tools. Alongside this, the author proposes related issues about information management in the supply chain, competition position and the scope of hinterland. This article, combined with the related theory of supply chain and performance evaluation, puts forward a set of relatively complete cooperation performance evaluations between seaports and dry ports, which provide scientific theory support for better cooperation.

In the production logistics system, man-machine-environment effecting factors mainly have the microclimate module (air temperature, humidity, atmospheric pressure, oxygen content, carbon dioxide, smoke and air velocity), the noise module (real-time noise and integrated noise), the illumination module (real-time illumination), the human physical work module (human blood pressure and heart rate) and so on. The mobile platform can be designed by the SolidWorks software, and be installed these relevant sensor instruments and signal transmission lines, in order to form hardware conditions of man-machine-environment system. The corresponding detection module can be designed by the LabVIEW software. It is necessary to take three times detection to demonstrate the reliability of data in the process of experiment. It is turned out that the data is in accordance with the relative standards, and the results are reliable.

This paper has analyzed earthquake with different design life and 50 years with the same design basis of probability guarantee, proposed seismic design life under different reference values recommended.

Previous studies have demonstrated that the growth of tumor cells may be inhibited by antisense oligonucleotides (ASODNs) targeted against human telomerase (hTR) or human telomerase reverse transcriptase (hTERT), resulting in antitumor activity in a wide variety of tumors. However, few studies have investigated the effect of hTERT gene-targeted ASODNs on telomerase activity and cell proliferation in human esophageal cancer. In the present study, an MTT assay was used to determine the growth inhibition rate of Eca-109 cells treated with a hTERT-targeted phosphorothioate-ASODN (PS-ASODN). An inverted microscope was used to observe the morphologic changes of the cells following treatment with 5 μM PS-ASODN for 10 days. Telomerase activity was detected using the silver staining semi-quantitative telomeric repeat amplification protocol (TRAP) assay. Following treatment with the PS-ASODN (1–5 μmol/l), the proliferation of the Eca-109 cells was inhibited. The differences in inhibition rate between the PS-ASODN and blank control groups were statistically significant (P

Java applications have proliferated rapidly in recent years, and the security issue in the source code seems to bring a great threat which cannot be ignored. SQL injection and cross-site scripting vulnerabilities, path traversal, and so on are common Java security vulnerabilities. These vulnerabilities are usually caused by improper handling of user input and we call them input validation vulnerabilities [1].In this paper, we propose a Java source code analysis method based on the taint tracking. By means of vulnerability pattern match, we keep track of the introduction of tainted data and its propagation in different contexts, leading to comprehensive and accurate test results. Actually, we have applied this method to some of the open-source Java projects. Compared to other similar software, our technique presents good feasibility and superiority.

Software source code homologous detection is also called software copy or software clone. It is used to detect the homologous in the source code, by which we can easily find the plagiarism in the code. In this paper, it will discuss the homology detection results based on Text, Token and Abstract Syntax Tree. And will compare the three techniques and raise a model to calculate similarity by synthesizing the results. This model is based on the analysis of a large number of experimental results. Comprehensive similarity calculation model can calculate the respective contribution of the three algorithms and realize integrated computation of similarity according to this respective contribution. Finally, we can get a comprehensive similarity by this integrated similarity calculation model to make the homology detection results more accurate and closer to the actual similarity.

In order to meet the measuring performance requirement of both high accuracy and large range when measuring the large-scale space angle formed by non-uniplanar lines quantitatively based on the engineering background of ammunition assembly angle test, we propose a measurement method that uses line structured laser as a common measurement reference and combined with vision inspection technique to achieve the measurement of large-scale space angle formed by non-uniplanar axes. Ammunition assembly angle have been measured accurately by using this method which provides a scientific approach for quality evaluation of that type of ammunition.

Polyvinyl alcohol fiber reinforced cement-based composites are a new kind of material based on micro mechanics design. It is produced by adding polyvinyl alcohol fiber in the cement-based composites. In efforts to study the mechanical properties of polyvinyl alcohol fiber reinforced cement-based composites, some specimens were tested to examine performances. According to experimental investigation on mechanical properties, the stress-strain relationship curves and failure patterns are obtained. The test indicates that polyvinyl alcohol fiber reinforced cement-based composites have better toughness and fracture energy, and it has superior physical mechanical performance.

Using the sodium citrate as ligands and adopting electric brush plating method, Re will be deposited together with Ni-P from the solution, and a complex brush plating of Ni-P-Re can be attained. It is discussed the effect of the rare earth Re3+ on the deposition rate, corrosion resistance and bonding strength of the Ni-P composite brush plating. Adding some appropriate Re3+ to the brush plating solution, the amorphous tissue can be obtained under the condition of the low phosphorus brush plating, which make the brush plating layer with high hardness and high abrasive resistance at the same time, binding force and corrosion resistance are improved, and greatly improve the performance of the brush plating.

Although supercritical CO2fracturing has incomparable advantages compared to hydraulic fracturing as a new recreating technology of shale gas reservoir, the application of this technology has been limited by the low viscosity and weak carrying capacity of proppant. It’s critical to enhance the viscosity of supercritical CO2by adding thickening agents. Thickening agents for supercritical CO2thathave been studied by researchers mainly contained polymers, small molecular compounds and surfactants. Thickening agents that match with CO2are characterized by low cohesive energy density, low polarity, high free volume and Lewis base. It’s necessary to study the interaction between thickening agents and CO2by molecular simulation to design inexpensive, green thickening agents which could increase the viscosity of supercritical CO2remarkably under low concentration.

Spinal cord injury (SCI) often results in motor disability concomitant with limit neuroplasticity; the underlying mechanism, however, is still unclear. This study established spinal cord transection rats model (T10), then performed cDNA microarray analysis and found that vimentin located in astrocytes was increased significantly in scar tissues after transection. To understand the role of vimentin and it's mechanism of regulation, RNA interference and luciferase assay were used. Vimentin knockdown in the scar tissues showed a significant improvement on locomotor function in hindlimbs, while vimentin overexpression exhibited an opposite effect. In vitro, vimentin downregulation or overexpression can effectively inhibit or increase astrogliosis, respectively. Moreover, by using biological informatics technology, we predicted that vimentin may be as the target of micRNA138 (miR-138), and confirmed that miR-138 could regulate vimentin by luciferase activity assay. The present results not only validated the exact role of vimentin in transected spinal cord, but also exhibited a novel regulation mechanism, in which miR-138 may regulate vimentin to promote neuroplasticity. It, therefore, provides a novel target for gene drug discovery based on miRNA-138 or vimentin for the treatment of SCI in the future clinic trial.

In the design of giant magnetostrictive material (GMM) actuator, the bias magnetic field is a vital part. For the use of GMM rod in the magnetostrictive actuator, there are two typical topology structures, in-line structure and coaxial structure. Although these structures have been used in the design of magnetostrictive actuator, little work has been done to compare the general features for concrete application conditions. In this paper, we use finite element analysis (FEA) as the main tool to analyze and compare these structures and come to a conclusion that, as to a diameter-limited actuator, when the length to diameter ratio of the rod is less than 5, coaxial actuator can provide more uniform magnetic field and less moving parts; when the length to diameter ratio of rod is 5, the field inhomogeneity is nearly equal, and coaxial actuator uses less moving parts and in-line actuator cost less permanent magnet (PM); when the length to diameter ratio of rod is more than 5, in-line actuator can provide more uniform magnetic field and use less PM.

In order to improve the productivity of the filing form materials continuously and automatically packaged line, the control methods for the manipulator and the mechanism which has the capacity of weight self-measuring and auto–filling to the packaged material were studied. The manipulator is a pneumatic control system, it is consists of three pneumatic cylinder circuits to implement the horizontal movements, vertical movements and the activities of picking up or putting down the materials on line. The material to be picked up by manipulator was weighed and displayed by a single chip microcomputer. The general control function of the system was carried out by a PLC unit. The structure changeable type of simulating human being intelligence control methods resulting in the real observing at the objective changes were studied and implemented to achieve the plant high in positioning accuracy and fast in response speed. The experiments were realized and the results showed that the working period time is less than 5.8s,the weight variation measured by single chip microcomputer is not more than 2 grams in 300 grams.

Based on the analysis of tactical characteristics testing of radio fuze, a conception of dummy isolation technology of high frequency and low frequency of electronic module was put forward. By Studying on the principium of fuze Doppler signal input and collection, the high frequency and the low frequency of electronic module was dummy isolated and one of the tactical characteristicsburst-height of radio fuze is nicely tested.

At the beginning of 21st century, with the growth of architecture and construction industry, many countries are having a great boom in crane industry. Still, there are some crane accidents, which usually cause startling devastation. As the rapid development of modern science and technology, especially dramatic improvement in internet, domestic and foreign scientists have taken advantages of advanced technology to exploit the safety monitoring system of tower cranes. Although the tower and tower arm are crucial targets of the safety monitoring system of tower cranes, the fact is that few scientists concentrating on the internal stress and strain in tower crane when it has been loaded. Hence, it is necessary to introduce some latest developments of the safety monitoring system of tower cranes in this text, presenting some existed problems and an advanced safety monitoring system basing on infrasonic emission technology.

Spinal cord injury causes sensory loss below the level of lesion. Synaptosomal-associated protein 25 (SNAP25) is a t-SNARE protein essential for exocytosis and neurotransmitter release, but its role in sensory functional recovery has not been determined. The aim of the present study is therefore to investigate whether SNAP25 can promote sensory recovery. By 2D proteomics, we found a downregulation of SNAP25 and then constructed two lentiviral vectors, Lv-exSNAP25 and Lv-shSNAP25, which allows efficient and stable RNAi-mediated silencing of endogenous SNAP25. Overexpression of SNAP25 enhanced neurite outgrowth in vitro and behavior response to thermal and mechanical stimuli in vivo, while the silencing of SNAP25 had the opposite effect. These results suggest that SNAP25 plays a crucial role in sensory functional recovery following spinal cord injury (SCI). Our study therefore provides a novel target for the management of SCI for sensory dysfunction. Refereed/Peer-reviewed

Oxidative stress is important in carcinogenesis and metastasis. Salidroside, a phenylpropanoid glycoside isolated from Rhodiola rosea L., shows potent antioxidant properties. The aim of the present study was to investigate the roles of salidroside in cell proliferation, the cell cycle, apoptosis, invasion and epithelial-mesenchymal transition (EMT) in A549 cells. The human alveolar adenocarcinoma cell line, A549, was incubated with various concentrations of salidroside (0, 1, 5, 10 and 20 μg/ml) and cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Propidium iodide (PI) staining was used to determine the cell cycle by flow cytometry. Cell apoptosis was detected by Annexin V-fluorescein isothiocyanate and PI double-staining, and tumor invasion was detected by Boyden chamber invasion assay. Western blot analysis was performed to detect the expression of EMT markers, Snail and phospho-p38. The results showed that salidroside significantly reduced the proliferation of A549 cells, inhibited cell cycle arrest in the G0/G1 phase and induced apoptosis. Salidroside inhibited transforming growth factor-β-induced tumor invasion and suppressed the protein expression of Snail. As an antioxidant, salidroside inhibited the intracellular reactive oxygen species (ROS) formation in a dose-dependent manner in A549 cells, and depletion of intracellular ROS by vitamin C suppressed apoptosis by salidroside treatment. Salidroside was also found to inhibit the expression of phospho-p38 in A549 cells. In conclusion, salidroside inhibits cell proliferation, the cell cycle and metastasis and induces apoptosis, which may be due to its interference in the intracellular ROS generation, thereby, downregulating the ROS-phospho-p38 signaling pathway.

By analyzing the working mechanism of timer of MCS-51 and waveform characteristics of the PWM pulse with dead-time, and proposed a new method of simultaneous control of two channels with dead-time PWM signal based on a single timer of MCS-51. This paper provided the programming idea and theoretical analysis, and this method has the advantages of simple structure, less occupied internal resources of the MCU, fast response, wide duty cycle range, waveform stabilization. By providing the driving signal for the experiment of drive circuit board DA962A4 for FF400R12KS4 type IGBT module, the validity and practicality of this method were examined.

One important objective of molecular assembly research is to create highly complex functional chemical systems capable of responding, adapting, and evolving. Compared with living systems, the synthetic systems are still rather primitive and are far from realizing those features. Nature is by far the most important source of inspiration for designing and creating such systems. In this critical review, we summarize an alternative approach, inspired by catalysis, to examine and describe some molecular assembly processes. A new term, "catassembly," is suggested to refer to the increase in the rate and control of a molecular assembly process. This term combines the words "catalysis" and "assembly," and identifiably retains the Greek root "cat-" of catalysis. The corresponding verb is "catassemble" and the noun is "catassembler", referring to the "helper" species. Catassembly in molecular assembly is a concept that is analogous to catalysis in chemical synthesis. After using several examples to illustrate the characteristics of catassembly, we discuss future methodological and theoretical developments. We also emphasize the significance of the synergy between chemical synthesis and molecular assembly, especially for hierarchical assembly systems. Because most efforts in the field of molecular assembly have been devoted to the design and synthesis of molecular building blocks, we wish to stress the apparently missing yet critical link to complex chemical systems, i.e., the design and utilization of molecular catassemblers to facilitate the formation of functional molecular assemblies from building blocks with high efficiency and selectivity. This rational control and accelerated method will promote the systems chemistry approach, and may expand the spectrum of molecular assembly from basic science to applications.