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Purpose The identification of infection at its early stage in vulnerable patients is challenging. This study aimed to investigate potential biomarkers to distinguish patients progressing to severe sepsis from those with uncomplicated sepsis. Materials and methods Serum samples were collected from sepsis patients admitted to the emergency department. The mRNA and protein levels of angiopoietin-2 (Ang-2), interleukin-10 (IL-10), heparin-binding protein (HBP), procalcitonin (PCT), adrenomedullin (ADM), and interleukin-6 (IL-6) were evaluated. Results Compared to those of healthy individuals (n = 47), mRNA levels of ANG2, IL10, HBP, PCT, and ADM were increased in patients who eventually developed sepsis. ANG2 was the only gene whose expression was significantly increased in patients developing severe sepsis than in those with uncomplicated sepsis. Serum levels of Ang-2, IL-10, HBP, PCT, and IL-6 were also increased in sepsis patients, but only Ang-2, HBP, and PCT were elevated in the serum of patients developing severe septic shock than in those with uncomplicated sepsis. Serum levels of Ang-2, HBP, and PCT were closely associated with the sequential organ failure assessment (SOFA) score of the patients. Conclusions These findings indicated that sustained elevation of Ang-2, HBP, and PCT were associated with severe infection in critically ill patients.

Inspired by green plants, artificial photosynthesis has become one of the most attractive approaches toward carbon dioxide (CO2 ) valorization. Semiconductor quantum dots (QDs) or dot-in-rod (DIR) nano-heterostructures have gained substantial research interest in multielectron photoredox reactions. However, fast electron-hole recombination or sluggish hole transfer and utilization remains unsatisfactory for their potential applications. Here, the first application of a well-designed ZnSe/CdS dot-on-rods (DORs) nano-heterostructure for efficient and selective CO2 photoreduction with H2 O as an electron donor is presented. In-depth spectroscopic studies reveal that surface-anchored ZnSe QDs not only assist ultrafast (≈2 ps) electron and hole separation, but also promote interfacial hole transfer participating in oxidative half-reactions. Surface photovoltage (SPV) spectroscopy provides a direct image of spatially separated electrons in CdS and holes in ZnSe. Therefore, ZnSe/CdS DORs photocatalyze CO2 to CO with a rate of ≈11.3 µmol g-1 h-1 and ≥85% selectivity, much higher than that of ZnSe/CdS DIRs or pristine CdS nanorods under identical conditions. Obviously, favored energy-level alignment and unique morphology balance the utilization of electrons and holes in this nano-heterostructure, thus enhancing the performance of artificial photosynthetic solar-to-chemical conversion.

This study aims to evaluate the role of chymostatin in paraquat-induced acute lung injury. Institute of Cancer Research mice were randomly distributed into the NS, DMSO, chymostatin, paraquat or chymostatin treatment groups. Six mice from each group were intraperitoneally injected with chloral hydrate at 0, 1, 2, 4, 8, 12, 24 and 48 h after treatment administration. Blood samples were collected through cardiac puncture. Lung tissues were stained with haematoxylin and eosin for the observation of lung histology. The degree of pulmonary oedema was determined on the basis of lung wet-to-dry ratio (W/D). The serum activity of cathepsin G was determined through substrate fluorescence assay. The serum levels of endothelial cell-specific molecule-1 (endocan), tumour necrosis factor-a (TNF-a), interleukin-1β (IL-1β), IL-6 and high-mobility group box protein 1 (HMGB1) were determined through enzyme-linked immunosorbent assay. The expression levels of endocan and nuclear NF-κBp65 in the lung were quantified through Western blot. Chymostatin alleviated the pathological changes associated with acute alveolitis in mice; decreased the lung W/D ratio, the activity of cathepsin G and the serum concentrations of TNF-a, IL-1β, IL-6 and HMGB1; and increased the serum concentration of endocan. Western blot results revealed that chymostatin up-regulated endocan expression and down-regulated nuclear NF-κBp65 expression in the lung. Chymostatin reversed the inflammatory effects of paraquat-induced lung injury by inhibiting cathepsin G activity to up-regulate endocan expression and indirectly inhibit NF-κBp65 activity.

Interleukin-17A (IL-17A) is involved in multiple inflammatory diseases. Our study was to investigate the role of IL-17A on acute lung injury (ALI) respectively induced by lipopolysaccharide (LPS) and paraquat (PQ) on mice. We built ALI mouse models respectively by single intraperitoneal (i.p.) injection with LPS or single gavage with PQ liquid. Two hours after the models were established, a dosage of neutralizing antibody was used to blockade IL-17A by i.p. injection. At 8, 24, and 48 h, the lung wet-to-dry ratio (W/D) was calculated and total protein in bronchoalveolar lavage fluid (BALF) was measured; hematoxylin-eosin staining was used to observe lung tissue pathological changes; inflammatory cells in BALF were recorded with a hemocytometer; cytokines were measured with enzyme-linked immunosorbent assay kits; immunohistochemistry examined the expression of IL-17A and activation of nuclear factor-κB p65 (NF-κB p65); and qPCR determined the expression of IL-17A mRNA. After being administered with LPS or PQ, all mice presented ALI pathological change; expression of IL-17A increased significantly. When blocking IL-17A with antibody, lung injury in both LPS- and PQ-administrated mice was attenuated. All the above tests decreased. Compared with those in PQ mice, IL-17A levels in LPS mice were higher. IL-17A involves the ALI induced by LPS or PQ and promotes the pathological process by activating NF-κB P65 and recruiting neutrophils, which enlarges the cascade effect of inflammation and injures lung tissues. And when blockading IL-17A with antibody, the ALI is alleviated. The reaction of IL-17A in the ALI induced by LPS is stronger than that by PQ.

Objective: Methods containing only clinical information fail to meet the needs of prediction of acute lung injury (ALI) because of the relatively low positive predictive value. This study aimed to investigate the feasibility of using biomarkers as predictors of ALI in populations with severe sepsis/septic shock and to explore difference among biomarkers after adjustment for potential confounders. Methods: Serum specimens were collected from patients with severe sepsis/septic shock (n = 172) presented to the emergency department. Patients should be ruled out from the study if they were already suffering from ALI or if they deteriorated into ALI within 6 hours after specimen collection. The development of ALI of the remaining patients was tracked. Results: Of all patients with severe sepsis/septic shock who encountered ALI more than 6 hours succeeding to specimen collection, 19 deteriorated into ALI. Elevation in serum interleukin 8 (IL-8) and Parkinson disease 7 (PARK7) levels had significant connection with higher risk of developing ALI ( P = .006; P = .0001). Sepsis treatment and vasopressor application led to a robust connection between PARK7 and succeeding ALI development. Patients who deteriorated into ALI were distinguished accurately from patients who avoided ALI using PARK7 or Lung Injury Prediction Score (LIPS; area under the receiver operating characteristic curve [AUROC], 0.73 and 0.72 for each). Combination of PARK7 and LIPS ameliorated AUROC to 0.86 (vs 0.73, P = .05). On the contrary, serum soluble receptor for advanced glycation end products and von Willebrand factor made no contribution to the prediction of ALI development. Conclusions: Patients with PARK7 or IL-8 levels above normal are more vulnerable to ALI. Patients vulnerable to ALI can be distinguished with the combination of serum biomarkers and clinical prediction scores. In addition, the early rise in PARK7 emphasizes the importance of endothelial injury in the early pathogenesis of ALI.

With the development of production and technology, the devices of oil refining, chemical, fertilizer and others are progressing to the direction of high parameters (high pressure, high temperature). Pressure vessels must be open, which will made the stress concentration problems more serious, and traditional design methods derived from empirically formula fails to meet the actual demand. In this paper, a theoretical result is calculated with a simplified model of the opening holes in cylindrical shell, verified by a group of solutions got by the ANSYS simulation. And it turns out that the result is rather satisfactory.

In this study, we reported on the construction of p–n junctions based on crystalline Ga-doped CdS–polycrystalline ZnTe nanostructures (NSs) for optoelectronic device application. The coaxial nano-heterojunction was fabricated by a two-step growth method. It is found that the absorption edge of CdS:Ga–ZnTe:Sb core–shell NSs red shifted to about 580 nm, compared with CdS nanowires (520 nm). The as-fabricated core–shell p–n junction exhibited obvious rectification characteristics with a low turn-on voltage of ∼0.25 V. What is more, it showed stable and repeatable photoresponse to 638 nm light illumination, with a responsivity and a detectivity of 1.55 × 103 A W−1 and 8.7 × 1013 cm Hz1/2 W−1, respectively, much higher than other photodetectors with similar device configurations. The generality of this study suggests that the present coaxial CdS:Ga–ZnTe:Sb core–shell nano-heterojunction will have great potential applications in future nano-optoelectronic devices.

In order to illustrate the mechanism of supporting, maintain the safety and keep the stable of underground projects, it is of great significance to study the transverse effect of bolted discontinuous rock mass. With a 3D model and corresponding physical simulation, analyzing the testing results of the bolt stress, rock stress and displacement discovers some new findings. Besides its reinforcing effect to the rock mass, the bolt has a negative effect on the discontinuous rock mass by its so-called ‘railway effect’ under shear loading. The finding of this bolt function will help to further understand of bolting mechanism and it is very important to raise the safety of bolt supporting design. Furthermore the effect grade is a positive correlativity with the bolt diameter, and the shear displacement is one of its necessary conditions.

Terzaghi equation is widely used in practice to determine Ultimate Bearing Capacity (UBC). Recent research indicates that exact solution of UBC could be got with the slip line method if the soil is ideal elastic-plastic material. In this paper, dimensionless UBC is gained using ABC software based on the slip line method and is compared with that by Terzagh equation with based on empirical formula. It shows that error of UBC is caused by empirical formula. However, the accuracy of UBC relates to safety and economy of the engineering. Given empirical formulas have a wide application in practice, the scope of application of the four classic empirical formulas is discussed in different range of allowable error. The applicable scope of the four classic empirical formulas within the margin of error is discussed and the results can facilitate the application of classic empirical formulas in practice.

ZnS0.59Se0.41 alloy nanowires were prepared on gold-coated Si substrates by the thermalevaporation of a mixture of ZnSe and ZnS powders. Field-effect transistors (FETs) constructed fromthe ZnS0.59Se0.41 NWs verified their p-type nature with a hole concentration of 3.1×1018 cm-3.Inaddition,the photoresponse indicates their potential for photoelectric applications.

Mechanical properties experiments of concrete after 0, 25, 50 and 75 freeze-thaw cycles under uniaxial and multiaixial compression were carried out. The uniaxial and multiaxial compressive strengths of ordinary concrete after freeze-thaw cycles were measured. According to the experiment results, the influence of freeze-thaw cycles on the ultimate compressive and tensile strength was analyzed systematically. The influence law of freeze-thaw cycles on compressive strength of concrete under multiaxial compression was obtained. The results indicate that the compressive strength of ordinary concrete after freeze-thaw cycles under multiaxial compression is higher than that under uniaxial compression, and the degree of improvement is depended on its stress ratio. This conclusion can propose theoretical foundation for design of concrete structures in cold environment

Applications of one-dimensional (1D) semiconductor nanostructures in nanoelectronics and nano-optoelectronics rely on the ability to rationally tune their electrical transport properties. Here we report the synthesis of single-crystalline Ag-doped ZnSe nanowires (NWs) by using silver sulfide (Ag2S) as the p-type dopant via a thermal evaporation method. The ZnSe:Ag NWs had the zinc blende structure with [11 ] growth orientation. Significantly, the conductivities of the NWs could be tuned over 9 orders of magnitude by adjusting the Ag doping levels. Field-effect transistors (FETs) constructed from the ZnSe:Ag NWs verified their p-type nature with a hole concentration of up to 2.1 × 1019 cm−3, which is the highest value achieved for p-type ZnSe nanostructures thus far. Schottky barrier diodes (SBDs) based on the ZnSe:Ag NW/ITO junctions exhibited remarkable rectifying behavior, with a rectification ratio of >107 and a small ideality factor of ∼1.29 at 320 K. Moreover, photovoltaic devices were fabricated from the ZnSe NW array/Si p–n heterojunctions by aligning the p-ZnSe NWs in a parallel fashion on a n-Si substrate. The device with a graphene top electrode showed a large fill factor (FF) of 61%, yielding a power conversion efficiency of ∼1.04%. The realization of p-type ZnSe NWs with tunable conductivity opens up opportunities for a host of high-performance nanoelectronic and nano-optoelectronic devices.

The impact resistance of steel fiber reinforced lightweight aggregate concrete was presented in a drop weight test. In this test, 5 groups of disc specimens with different steel fiber volumes including 0.0%, 0.5%, 1.0%, 1.5% and 2.0% were tested. The experimental results indicated that the impact resistance of lightweight aggregate concrete is improved with the increase in fiber volume. As the variation in experimental results, a statistical evaluation was performed to study the influence of impact resistance of steel fiber reinforced lightweight aggregate concrete with different steel fiber volumes. Further more, the impact resistance was simulated with probability distribution by Log-normal method. And the goodnees-of-fit tests indicate that the Log-normal method has good fitness to the impact resistance of steel fiber reinforced lightweight aggregate concrete.

Since high strength of lightweight aggregate concrete leads to increased brittleness, fiber reinforcement should be considered for improving strength and ductility. 5 groups of SFLWC specimens with different steel fiber volumes including 0.0%, 0.5%, 1.0%, 1.5% and 2.0% were tested to investigate the effect of steel fiber content on the static mechanical properties and impact resistance of lightweight aggregate concrete. The static mechanical properties include the prismatic compressive strength, splitting tensile strength, first-crack flexural strength, flexural strength, and flexural toughness, etc. The experimental results indicated that addition of steel fiber can greatly improve such mechanical properties as the splitting tensile strength, flexural strength, flexural toughness and impact resistance, but leads to a little effect on compressive strength. Further more, the author suggests the feasible volume ratio of this kind of steel fiber is 1-1.5%.

Based on numerical simulation of computing Software ANSYS, the curve of arching coefficient variation of pressure arch due to actual mining was analyzed aiming to a special mining face, the law of stress transfer and change in surrounding rock was discussed, and the evolving features and characteristics of pressure arch was obtained. The analysis and discussion show the following facts: Arch body will become thicker and stress in the arch body increases with working face’s driving distance increasing; the morphology of pressure arch transits from ellipsoid with long axis in the vertical direction to ellipsoid with long axis in the horizontal direction along the trend of working face; along the tendency of working face, the morphology of pressure arch is a ellipsoid with long axis in the vertical direction.

One of the most popular pre-reinforcement structures in the construction of tunnels through weak grounds would be the pipe roof reinforcement. This composite structure consists on installing, prior to the excavation of a length of tunnel, a series of pipes, either parallel to the tunnel axis or at a certain angle with it. By injecting grout through the pipes, the ground in between the pipes is stiffened and the pipes are connected, creating a kind of ‘umbrella’ above the area to be excavated. In this paper, by modifying the upper bound solution for tunnel face stability, the three-dimensional model for expressing the tunnel face stability with pipe roof reinforcement was established. For a typical example, the solutions computed by the proposed approach were compared with the results given by wedge model, trapezoid wedge model and centrifugal-model test to verify the reasonability of the method. It is shown that the calculation results of limit analysis are in close agreement with test results.

The solidification process of a conventional superalloy, IN718, was investigated by confocal scanning laser microscope (CSLM). The liquid fraction during solidification was obtained as a function of real time and temperature in reference with the in-situ observation. The characteristics of L→γ transformation were analyzed and the γ growing rate of each stage was also calculated. Scheil equation was employed to predict the segregation behavior, and the predict results are in consistence with the experimental results. As a result, the confocal scanning laser microscope shows a great potential for solidification process research.

Stress wave test technique has broad prospects because of the long distance, large scale and relatively low cost. This paper studies the stress wave propagation characteristics in the butt weld joints in the case of external symmetrical impact. The stress wave propagating before and after the joints is measured by dynamic strain gauge. Then model analysis and simulation is applied to research stress wave. The results show the loss of stress wave is small. After spectrum analysis, the change of propagating stress wave can be detected.

It has economical and social value to build energy-saving architectures. Foamed concrete is commonly used as non-load bearing structure to save energy of buildings. With reinforcement of fiber foamed concrete can be used as load bearing structure to build architectures. The load bearing structure of fiber reinforced foamed has ability of self thermal insulation to get the aim of energy-saving. In the paper the excellence and disadvantage of foamed concrete is summarized. Methods are given to build the energy-saving architecture with self thermal insulation structure of fiber reinforced foamed concrete in new formwork. The building technology will be applied in new countryside construction in China.

Based on analysis of basic photonic Doppler velocimetry (PDV), a formula to measure velocity variation in a single cycle is put forward. PDV has been improved in three aspects, namely, the laser, the detector and the data processing. A measurement system for velocity of the initial stage of a shock motion has been demonstrated. Instantaneous velocity measurements have been performed. The experimental results have a good agreement with the values obtained from the accelerometer. Compared with the traditional fringe method, the proposed method in this paper can identify instantaneous velocity variation. So it is particularly suitable for measuring the velocity in the transient acceleration process of shock waves and detonation waves.

Alloy 718 has a very long history, it is still used extensively, which accounts for more than 50% of commercial superalloy productions in the world. The reason is that Alloy 718 exhibits good strength, excellent weldability and lastly, but most importantly, reasonable cost. Recently, confocal scanning laser microscope (CSLM) offers a convenient way for conducting a real-time and continuous in-situ observation of phase transformations at high temperatures. Several studies using CSLM have been reported for low carbon steel, stainless steel and metallic glass materials. The aim of this paper is to study the solidification behavior of Alloy 718 using confocal scanning laser microscope. In addition to the in-situ observation of solidification at different cooling rates, the analysis of microstructure evolution was conducted by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results show that the cooling rate has a great impact on the solidification behavior of Alloy 718. Variation of secondary dendrite arm spacing, morphology change in MC carbide, and Laves phase after solidification at different cooling rates are studied in details. Introduction Alloy 718 is an age-hardenable wrought superalloy used for elevated temperature gas-turbine applications, which is famous for its excellent balance of properties and reasonable cost, accounting for more than 50% of commercial superalloy productions in the world [1]. With the development of land-based power generation and aircraft propulsion, scaling-up of components has become the necessity. In response to market demands the size of Alloy 718 ingot produced by VIM-ESR-VAR triple melting has increased markedly over the past 10 years [2-7]. However, the solutes segregation problem, mainly niobium segregation, is a big issue for producing large size Alloy 718 ingots. Particularly, some macrosegregations such as freckles and white spots formed during the solidification process may lead to failure of entire ingot. Therefore the indepth studies of solidification behavior of Alloy 718 are still needed.

Stock market forecasting has attracted a lot of research interests in previous literature. Traditionally, the autoregressive moving average (ARMA) model has been one of the most widely used linear models in time series forecasting. However, the ARMA model cannot easily capture the nonlinear patterns. And recent studies have shown that artificial neural networks (ANN) method achieved better performance than traditional statistical ones. ANN approaches have, however, suffered from difficulties with generalization, producing models that can overfit the data. Support vector machines (SVMs), a novel neural network technique, have been successfully applied in solving nonlinear regression estimation problems. Therefore, this investigation proposes a hybrid methodology that exploits the unique strength of the ARMA model and the SVMs model in the stock market forecasting problem in an attempt to provide a model with better explanatory power. Real data sets of stock market were used to examine the forecasting accuracy of the proposed model. The results of computational tests are very promising.

Fully leaky optical-guided mode was employed to determine the difference in the splay and bend flexoelectric coefficient (e1–e3) in negative nematic liquid crystal MS-N01300-000. The experimental curves of reflectivity versus internal angle (angle of incident light to the liquid crystal) were obtained when a laser beam passed through the hybrid-aligned nematic in-plane switching liquid crystal cell; the cell was embedded in pyramid-coupled waveguide with different alternating current (AC) and direct current (DC) voltages. The curves of the applied DC with voltage similar to that of AC shift to the left or the right. Experimental results were then compared with theoretical results derived from elastic continuum theory and multi-layer optical theory of liquid crystals. The approximate value of the flexoelectric coefficient (e1–e3) of MS-N01300-000 is 9.0 × 10−11 C/m.