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Chlorinated aromatics and alkanes have important use value because of their flame retardancy，but they need to be monitored when used in recycled pulp. This paper report the use of palladium acetate/ Activated carbon activated by nitric acid as an online catalyst in the determination of chlorinated aromatics and chlorinated alkanes in recycled paper products with Gas Chromatography-Tandem Mass Spectrometry method, by which significantly improve the sensitivity of the method and dramatically lower the detection limits.

Perched water zone occurs in the subsurface of the slope under heavy rainfall or above an impeding layer with relatively low permeability. It causes a decrease in the shear strength of the soil and the increase in the loading on the slope. As the most used method of estimate the slope stability, the limit equilibrium method considers the influence of rainfall infiltration on the slope stability by increasing the underground water table and decreasing the shear strength parameters on the slip surface. However, the contribution of perched pore water pressure is usually ignored. To incorporate the effect of perched water pressure into the stability analysis, the Bishop’s simplified method and Janbu’s simplified method are modified to perform stability analysis in the situation of circular and composite slip surfaces, respectively. The detailed methodology and numerical implement procedure are presented. Then, three examples are adopted to verify the proposed methods and to investigate the impact of the perched water zone on slope stability. The results show that the program developed in this study has considerable accuracy compared to commercial software. The pore water pressure in the perched water zone has important impacts on slope stability, especially when the depth of the perched water zone is greater than 4 m. Ignoring the perched pore water pressure in the slope stability analysis might overestimate the safety status of the slope.

Solving the undesirable intermittence and fluctuation problems of renewable energy production needs complementary energy storage on a large scale. Compressed air energy storage in caverns (CAES-C) has been verified as an effective technique. To further improve the energy storage efficiency and save costs, compressed air energy storage in aquifers (CAES-A) and compressed carbon dioxide energy storage in aquifers (CCES-A) were proposed successively. However, the operation performances of CCES-A, especially the hydrodynamic and thermodynamic properties of its underground components (the wellbore-reservoir system), are not clear. Here we introduce a coupled wellbore and reservoir model, T2WELL-ECO2N, initially used for geologic carbon sequestration simulation, for simulating the dynamics of CO2 injection and production through wellbore in both the construction and operation stages of CCES-A. The temperature, pressure, CO2 saturation and transfer, energy efficiency, maximum system cycle times, total stress change induced by CO2 injection in aquifer, and sensitivity analysis of permeability in the wellbore-reservoir system of the designed CCES-A are comprehensively studied. The simulation results show that during the operation stage the CO2 is supercritical and fluctuates in both wellbore and aquifer where the CO2 saturation decreases and CO2 bubble generally moves to the central and lower parts of the target aquifer rather than the outside direction. The system itself effectively alleviates the loss of CO2 mass from the side walls of the aquifer. The fact that the cold CO2 zone in the aquifer can continuously receive energy by heat transfer from the surroundings helps the energy efficiency of the CCES-A system gradually increase, and even reach 1.1. The system cycle times exceed 1000 days when the aquifer permeability is larger than 5.0 × 10−13 m2, indicating that CCES-A needs less time to reconstruct the cushion gas compared with CAES-A and can lower the operating cost accordingly.

Lined rock cavern at shallow depth is identified as a promising alternative and cost-effective solution for air storage of large-scale compressed air energy storage (CAES) plant. To better understand the thermodynamic process of the compressed air in the underground cavern and the response of the surrounding rock during air charging and discharging phases, a small-scale pilot cavern with concrete liner and fiber-reinforced plastic (FRP) sealing layer was constructed in China. The test program includes one trial charging test, eight short-term charging tests, and one long-term charging test. Numerical simulations were carried out along with the experiments. The results show that the air pressure in the pilot cavern increased/decreased approximately linearly during the charging/discharging phase when the air was injected/released at a constant mass rate. The heat exchanging system could maintain the temperature of the compressed air in the cavern in a designed range. Excellent sealing performance of the FRP was validated in the test, with only 3.2% air mass leaked during the high-pressure storage phase. The influence of the high air pressure on the surrounding rock was limited and only elastic deformation was observed in all the tests. Good quality of rock mass could guarantee the structural safety of the underground cavern under high inner pressure. Generally, there are reasonable agreements between the numerical simulation and the results of the experiment. The study confirms the feasibility of CAES in lined rock caverns at shallow depth.

Two configurations of the furan–CF3Cl complex have been observed by high-resolution rotational spectroscopy. One is characterized by a dominant Cl lone pair⋯π* aromatic interaction and the other is stabilized by a C–Cl···π-C=C- halogen bond. This is the first rotational spectroscopic evidence, to the best of our knowledge, that shows how a complexation with a partner like CF3Cl (the weak lone pair belt of Cl, to be more specific) can modulate both the aromatic π* and diene π characters of a heteroaromatic molecule in the formation of non-covalent interactions. The results emphasize the partner molecules’ role in modulating the π electron structure and will not only deepen our understanding on non-covalent interactions but also lead to better designs of heteroaromatic-based drugs and materials.

A mild strategy for fabricating nanoporous silver (np-Ag) pieces was reported via preparation of Ag–Ga alloys in relatively low temperature and subsequent electrochemical dealloying in nitric acid (HNO3) aqueous solution. After selectively etching Ga out of the Ag–Ga alloy, a typical three-dimensional (3D) bicontinuous nanoporous structure with a pore size of ∼67.21–159.33 nm was observed. A series of studies have shown that the addition of sodium dodecyl sulfate (SDS) results in minimum pore size. The coarsen exponent (n) is 1.61, and the activation energy was calculated to be 27.04 kJ mol−1. The ζ′-AgGa alloy prepared at low temperature can be used as the precursor for the preparation of fine np-Ags, and this method provides a new strategy for the industrial production of dealloyed np-Ag.

The key to preventing the seepage of hydrocarbons from underground water-sealed oil storage facilities is to maintain a certain thickness of groundwater on the top of the caverns so that the groundwater pressure can maintain their tightness. However, the presence of fractures in the rockmass that surrounds the caverns complicates the calculation of the seepage field in the oil storage area. Conventional two-dimensional or equivalent three-dimensional seepage models cannot accurately reflect the impact of the fractures on the seepage field. Therefore, in this study, a dual-porosity medium modeling approach was used to develop an unsteady-state seepage model using the three-dimensional discrete element software 3DEC. The model was developed to assess the effect of grouting on the rock mass that surrounds oil storage caverns that took into account the possible presence of non-persistent fractures. Thus, the simulation of the three-dimensional seepage field of large-scale water-sealed oil storage caverns was realized. The three-dimensional seepage field evolution law and seepage control effect under different working conditions during the construction and storage phases were studied. The results can provide a particular reference for the construction and operation of large-scale underground water-sealed oil storage caverns.

BACKGROUND Uveal melanoma (UM) is the most common intraocular malignancy, and the prognosis of patients with advanced stage of UM is very dismal. The T cell receptor ectopic expression of butyrophilin-like 9 (BTNL9) has been observed in several types of cancers, but the expression and clinical significance of BTNL9 in UM is unclear. MATERIAL AND METHODS In our study, we detected the expression of BTNL9 in 6 pairs of UM tissues and adjacent tissues using quantitative real-time polymerase chain reaction (qRT-PCR), and further investigated BTNL9 expression with immunohistochemistry (IHC) in a retrospective cohort consisted of 62 UM patients. The correlations between BNTL9 expression and clinicopathological factors were analyzed with Fisher's test, and the prognostic significance of BTNL9 was evaluated with univariate analysis and multivariate analysis. Using experiments in vitro, we investigated the function of BTNL9 in UM proliferation and invasion. RESULTS BTNL9 mRNAs in adjacent tissues were remarkably higher than in UM tissues. The percentages of BTNL9 low expression and high expression were 56.45% and 43.55%, respectively. High expression of BTNL9 was significantly associated with favorable prognosis of UM. BTNL9 expression was identified as a prognostic biomarker predicting better outcome of UM patients. Moreover, BTNL9 could suppress invasion instead of proliferation in melanoma cell line. CONCLUSIONS BTNL9 was a favorable prognostic factor of UM and it could suppress invasion of UM, suggesting that BTNL9 detection could help stratify high-risk patients with UM after operation and guide more precise surveillance and treatment.

In this paper, the random response of nonlinear dynamic systems with fractional order term are examined. In this context, an efficient approach called CR-FPK method is proposed to numerically obtain transient stochastic response for those nonlinear systems under white-noise excitation in which damping is of fractional order. This approach is based on the extension of stochastic averaging method and the process of cell renormalization. By first revisit the process of equivalent linearization and stochastic averaging, the Markov property of envelope response is firstly settled. Then the idea of cell renormalization is introduced to reconstruct the derivative moments and the corresponding Fokker–Planck–Kolmogorov (FPK) equation of the envelope process. The transient and stationary probability density function (PDF) of the envelope process is finally obtained by solving the transient FPK equation. The reliability of this method is verified by using the benchmark results of analytical method and Monte Carlo Simulation. The conclusion and the issues to be further studied are presented in the last part.

Pervasive unsafe behaviors of construction workers are the primary cause of accidents on construction job sites. The workers' safety-related behaviors are subject to a variety of factors, such as interactions with coworkers and interventions by management teams. The impacts of these factors have attracted considerable attention in academia but are yet to be fully examined. To provide a quantitative assessment of these impacts and their managerial implications in practice, an agent-based modeling approach of construction safety-related behaviors, which adopts a bottom-up architecture, is proposed in this research. This approach regards safety performance as an emergent property of the behaviors and interactions of construction workers and management teams. The development of the agent-based model is based on a range of theoretical and empirical evidence, including a cognitive analysis model for modeling worker behaviors, and site observations and surveys for the design of simulated working environment and tasks, as well as the modeling of individual behaviors and interactions. Four managerial scenarios are simulated using the proposed approach. Based on the simulation results, the effects of a number of managerial factors on the safety performance of construction workers are examined. These factors include duties of supervisors, the competency and inspection strategy of safety officers, the frequency of safety training, senior managers' involvement in safety activities and emphasis on safety goals. The effects of these factors are examined in a quantitative manner, and relevant implications for construction safety management practice are discussed. The findings prove that agent-based modeling is an effective approach for analyzing the characteristics and patterns of construction safety-related behaviors and assessing possible safety management strategies.

Introduction: Uveal melanoma is one of the most common primary intraocular malignant tumors with poor prognosis and limited treatments. Programmed cell death receptor-1 (PD-1) blockade represents the primary treatment strategy of immune checkpoint inhibition; however, there is a lack of studies on whether PD-1 expression in primary (ocular) uveal melanoma affects tumor progression. Methods: PD-1 expression in 82 cases of primary (ocular) uveal melanoma was detected by immunohistochemistry. The clinical significance of PD-1 expression was evaluated using univariate and multivariate analysis. PD-1 overexpression and knockdown studies were conducted in C918 and Mum-2B cell lines to analyze the effect of PD-1 expression on tumor cell proliferation and intracellular cell signaling transduction. real-time qPCR (RT-qPCR) and western blot analysis were performed to investigate the gene expression level. CCK8 assays were performed to examine the cell proliferation ability. Results: High expression of primary (ocular) intratumor PD-1 was associated with poor patient survival. Moreover, PD-1 expression was correlated with the largest tumor diameter. PD-1 expression and optic nerve invasion were independent prognostic risk factors. PD-1 overexpression in uveal melanoma cell lines promoted tumor cell proliferation, while knockdown of PD-1 inhibited cell proliferation capacity. Conclusion: Our study established the role of PD-1 in the progression of uveal melanoma and provided a new potential treatment selection for uveal melanoma.

Supplemental material, Supplemental_Figure1 for PD-1 expression on uveal melanoma induces tumor proliferation and predicts poor patient survival by Zhongming Jiang, Yuexiang Yan, Juan Dong and Lingling Duan in The International Journal of Biological Markers

BACKGROUND BCL2 19 kD protein-interacting protein 3 (BNIP3) is a BH3-containing protein of the BCL-2 family; it can regulate cell death, autophagy, and cytoprotection. The upregulation of BNIP3 has been reported to relate to progression and poor prognosis in different cancer types. However, the clinical significance of BNIP3 in uveal melanoma (UM) is still unknown. MATERIAL AND METHODS In our study, 47 patients with UM were enrolled; the expression of BNIP3 was detected with immunohistochemistry. According to BNIP3 immunohistochemical scores, the patients were divided into BNIP3 high- and low-expression subgroups. The correlation between the expression of BNIP3 and clinicopathological factors was evaluated with Fisher's test; the associations with survival rates were analyzed with log-rank test. The independent prognostic factors were identified with the Cox-regression model. RESULTS BNIP3 was mainly localized in the cytoplasm, and high expression of BNIP3 accounted for 31.9% (15/47) of the patients in our study. High expression of BNIP3 was demonstrated to be significantly associated with more pigment (P=0.018) and deeper scleral invasion (P=0.013). High expression of BNIP3 was also correlated with lower overall survival rate (P=0.006). Multivariate analysis confirmed positive ciliary body involvement and lymphatic infiltration as independent prognostic factors. CONCLUSIONS High expression of BNIP3 was significantly associated with poor prognosis of patients with UM, indicating that BNIP3 detection could help stratify high-risk patients and identify new therapies targeting BNIP3 as a promising approach to treat UM.

Stochastic dynamic analysis of the nonlinear system is an open research question which has drawn many scholars’ attention for its importance and challenge. Fokker–Planck–Kolmogorov (FPK) equation is of great significance because of its theoretical strictness and computational accuracy. However, practical difficulties with the FPK method appear when the analysis of multi-degree-of-freedom (MDOF) with more general nonlinearity is required. In the present paper, by invoking the idea of equivalence of probability flux, the general high-dimensional FPK equation related to MDOF system is reduced to one-dimensional FPK equation. Then a cell renormalized method (CRM) which is based on the numerical reconstruction of the derived moments of FPK equation is introduced by coarsening the continuous state space into a discretized region of cells. Then the cell renormalized FPK (CR-FPK) equation is solved by difference method. Three numerical examples are illustrated and the effectiveness of proposed method is assessed and verified. Keywords: Data-driven computational mechanics, FPK equation, Dimension reduction, Cell renormalization, Model-free

For the uncertainty quantification in structural dynamics, random simulate methods such as Monte Carlo Simulation, Probability Density Evolution Method (Le and Chen, 2009) and metamodel method (Hastie et al., 2005) [2] are extensively used because of their usability and universality. Unfortunately, the required computational resource for structural stochastic analysis is still a burdensome task especially structures are involved in nonlinearity and high dimensional uncertainty. The so called “curse of dimension” problem means the cost of performing a reliable reliability analysis increases exponentially with the dimension. In present paper, a supervised dimension reduction methodology named Active Subspace Method (Constantine, 2015) is introduced to deal with the high dimension problem of structural reliability. GF-discrepancy based point set is employed to exploit the hidden low-dimensional structure in the mapping from input to the quantity of interest (QOI), a kriging metamodel (Kaymaz, 2005) with higher accuracy and efficiency can be constructed on the low-dimensional subspace. Further, the extreme-value reliability of structure is calculated effectively by incorporating into probability density evolution method based extreme-value system reliability (Li et al., 2007). The proposed approach is then applied to a theoretical four branches system with two-dimensional random variable and a 6-DOF Bouc-Wen nonlinear numerical model with 20-dimension random variable. The results show that the Active Subspace Kriging (ASK) method significantly improved the result of extreme-value reliability analysis for stochastic nonlinear structures, in which high dimensional randomness problem is involved.

We theoretically investigate the enhanced charge-dependent generation of the optical second-order sidebands (OSS) in a gain-cavity-assisted optomechanical (GCAOM) system coupled to a charged object. The hybrid optomechanical system is coherently driven by an external two-tone laser field which consists of a continuous-wave pump field and a pulsed probe field. Beyond the conventional linearized description of optomechanical interactions, the nonlinear optomechanical interactions are included in the Heisenberg-Langevin equations and are treated analytically by means of the perturbation method. It is shown that an assisted gain cavity can significantly enhance the OSS generation and can also lead to higher charge dependence of the output OSS spectrum than that achieved from a lossy cavity optomechanical system. Subsequently we discuss the application of such a GCAOM system as a family of high-sensitivity sensor for measuring the charges. Using experimentally achievable parameters, we identify the conditions under which the assisted gain cavity allows us to enhance the OSS generation and improve sensitivity of the sensor beyond what is achievable in a lossy cavity optomechanical system. The present investigation may provide a route toward modulating the nonlinear optical properties of the electro-optic hybrid system, as well as to guide the design of sensitive devices.

A new high-order NMM is described in detail. The derivative degrees of freedom with physical meaning, which have been used in discontinuous deformation analysis (DDA), continue to be employed in the NMM. A new local displacement approximation, whose order is promoted, is suggested for the NMM. The local approximation makes the NMM get rid of the issue of the linear dependence (LD) and makes the NMM possess the substantive characteristic of a continuous stress field at the "star points". An existing stress post-processing technology, which does not lead to a forfeit of the abovementioned essential characteristic, is reinvented to improve the stress accuracy of the displacement-based method. The recurrence formula of the initial stress matrix is also generalized and revised to adapt to the proposed NMM. Moreover, a simplified inhibition approach is presented to deal with the free expansion (FE) problem of manifold element. Several typical examples are given to demonstrate the effectiveness of the proposed NMM. (C) 2015 Elsevier Ltd. All rights reserved.

The numerical manifold method (NMM) is a unified framework that is used to describe continuous and discontinuous problems. The NMM is derived based on the finite cover approximation theory and gains its name after the mathematical notion of manifold. It is also a method based on the partition of unity (PU) and it introduces two cover systems: the mathematical cover (MC) and the physical cover (PC). There are two approaches for constructing high-order approximations. The first approach involves a non-constant PU function and non-constant local approximations. This results in the linear dependence (LD) problem and leads to the singularity in a global matrix. The second approach involves a higher PU function and constant local approximations. The increase in the order of approximations should go along with the increase in star but the LD problem can be avoided completely in theory. In this paper, a new high-order NMM with nine-node triangular meshes is proposed. The upgrade from first-order NMM to high-order NMM is illustrated in detail. Moreover, the initial stress matrix is analyzed in detail. The effectiveness and accuracy of the proposed high-order NMM are validated using several typical examples. The proposed high-order NMM supplements the existing family of non-LD high- and low-order NMM under MC with triangular meshes. (C) 2015 Elsevier Ltd. All rights reserved.

Background rs11801299 and rs1380576, two novel polymorphisms in MDM4 gene, have been investigated in several different cancer types. However, the role of these two polymorphisms in retinoblastoma (RB) remains unclear. Methods A total of 126 patients with primary RB and 148 age-/gender-matched controls were included in this retrospective study. The frequency of rs11801299 and rs1380576 were determined between RB patients and controls. The association of these two polymorphisms with clinicopathological characteristics, prognosis were further evaluated. Results AA genotype at rs11801299 was significantly associated with an increased risk of developing RB (OR = 2.06, 95%CI 1.09–3.90). The possibility of developing RB was also significantly increased in individuals with A allele at rs11801299 (OR = 1.49, 95%CI 1.06–2.08). RB patients carrying AA genotype and A allele at rs11801299 were more likely to have tumor invasion and poor differentiation. As for rs1380576, a significantly lower risk of developing RB was observed in patients with G allele (CG + GG) compared with wild-type CC genotype (OR = 0.59, 95%CI 0.36–3.95). RB patients with GG genotype or G allele had a lower risk of developing highly aggressive cancer. Kaplan-Meier curves and log-rank results revealed that RB patients carrying AA genotype or A allele (AA + GA) at rs11801299 had significantly poorer prognosis. Multivariate COX analysis showed that the rs11801299 G allele was associated with decreased survival but was not an independent prognostic factor. Conclusion rs11801299 was significantly associated with RB risk, pathological differentiation, tumor aggressiveness and poor prognosis.

Unusual local arrangements of protein in Ramachandran space are not well represented by standard geometry tools used in either protein structure refinement using simple harmonic geometry restraints or in protein simulations using molecular mechanics force fields. In contrast, quantum chemical computations using small poly-peptide molecular models can predict accurate geometries for any well-defined backbone Ramachandran orientation. For conformations along transition regions-ϕ from -60 to 60°-a very good agreement with representative high-resolution experimental X-ray (≤1.5 A) protein structures is obtained for both backbone C-1 -N-Cα angle and the nonbonded O-1 …C distance, while "standard geometry" leads to the "clashing" of O…C atoms and Amber FF99SB predicts distances too large by about 0.15 A. These results confirm that quantum chemistry computations add valuable support for detailed analysis of local structural arrangements in proteins, providing improved or missing data for less understood high-energy or unusual regions.

In this paper, a deep learning classification model is proposed for automatically detecting the marine oil spill in Lanset-7 and Lanset-8 images, which can combine fully convolutional network (FCN) with Resnet and Googlenet respectively. The classification algorithms, i.e. FCN-Googlenet and FCN-ResNet are compared to the state-of-the-art Support Vector Machine (SVM) method. The experimental results show that our FCN-Googlenet and FCN-ResNet models outperform other approaches with a significant improvement. Moreover, our methods are more flexible in that no restriction on the size of input image is required in our algorithmic setups, which is more suitable in real applications.

Fatigue is believed to have a negative effect on workers’ safety performance. The current fatigue studies in construction have relied on questionnaire or interview survey, and due to certain limitations of such research method, the changing patterns of errors and the types of errors associated with different levels of fatigue are not well understood. By viewing an unsafe behavior as a cognitive failure, this research proposes an experimental method to study the effect of fatigue on construction workers’ safety performance. First, the research designed a typical manual handling task to simulate the actual construction work. The participant’s fatigue level could be measured by a Fatigue Assessment Scale for Construction Workers (FASCW), and the participant’s safety performance could be measured by monitoring the participant’s errors when performing the tasks. Second, a pilot study was conducted to show that the experimental tasks could induce fatigue effectively, and workers made more errors in a fatigue state. Third, the formal study found that the fatigue level of 20 was a critical point from where the effect of fatigue began to emerge. When a worker’s fatigue level exceeded 20, there was a linear relationship between fatigue levels and error rates. In terms of error types, when at a relatively low fatigue level above 20, a worker’s errors were mainly due to the failure of hazard perception. But as fatigue accumulated, its impact on the worker’s capacity of motor control became significant. Relevant implications derived from the experimental findings for safety management are also discussed.

The effect of single nucleotide polymorphisms (SNPs) at MDM2 has been investigated in several cancer types. Three MDM2 SNPs(rs937283, rs2270744 and rs769412) have previously been suggested to be positively correlated with cancer. In this study, we aimed to explore the association of rs937283, rs2270744 and rs769412 polymorphisms with retinoblastoma (RB) risk, clinicopathological characteristics, and prognosis. Compared with wild-type genotype AA at rs937283, individuals carrying AG and GG genotype had a significantly increased risk for developing RB (OR = 1.86, 95% CI 1.13–3.08; OR = 2.48, 95% CI 1.10–5.62, respectively). RB patients with allele G at rs937283 were more susceptible to invasion and high tumor aggression (OR = 2.42, 95% CI 1.43–4.11; OR = 2.15, 95% CI 1.27–3.64, respectively). Kaplan-Meier curves and log-rank results revealed that RB patients harboring genotype GG and G allele at rs937283 had worse survival (P P in vitro. In vivo, we found that MDM2 mRNA and protein were overexpressed in individuals who carried the G allele at rs937283. This study suggested that the MDM2 rs937283 polymorphism is a novel functional SNP both in vitro and in vivo as well as a biomarker for poor prognosis in RB.

To explore the variation of permeability and deformation behaviors of a fractured rock mass in high water pressure, a high pressure permeability test (HPPT), including measuring sensors of pore water pressure and displacement of the rock mass, was designed according to the hydrogeological condition of Heimifeng pumped storage power station. With the assumption of radial water flow pattern in the rock mass during the HPPT, a theoretical formula was presented to estimate the coefficient of permeability of the rock mass using water pressures in injection and measuring boreholes. The variation in permeability of the rock mass with the injected water pressure was studied according to the suggested formula. By fitting the relationship between the coefficient of permeability and the injected water pressure, a mathematical expression was obtained and used in the numerical simulations. For a better understanding of the relationship between the pore water pressure and the displacement of the rock mass, a 3D numerical method based on a coupled hydro-mechanical theory was employed to simulate the response of the rock mass during the test. By comparison of the calculated and measured data of pore water pressure and displacement, the deformation behaviors of the rock mass were analyzed. It is shown that the variation of displacement in the fractured rock mass is caused by water flow passing through it under high water pressure, and the rock deformation during the test could be calculated by using the coupled hydro-mechanical model.

Objective: To investigate the feasibility of using attenuated Salmonella typhi as an in vivo delivery vector for multidrug-resistance gene (MDR1) small interference RNA (siRNA) in a mouse model bearing human tongue squamous cell cancer tumors. This technique may represent a novel and effective route for the in vivo administration of RNA interference therapy against malignant tumors. Methods: The cisplatin (DDP)-resistant human tongue squamous cell carcinoma cell line Tca8113/DDP, which highly expresses the MDR1 gene, was established by exposure to gradually increasing concentrations of cisplatin. MDR1 siRNA expression plasmids were constructed and transformed into attenuated Salmonella typhi strain SL7207. Tca8113/DDP cells were infected with recombinant salmonella and expression of the MDR1 gene encoded P-glycoprotein (P-gp) product was detected. Tca8113/DDP tumor-bearing nude mice were established by inoculation by gavage administration of recombinant salmonella and were simultaneously injected intraper...

The unsafe behaviors of construction workers are often the immediate causes of construction accidents, but the underlying causation of such behaviors are not well understood. This research regards the management of construction safety as a system, and seeks to use system dynamics to demonstrate how the system influences construction workers in terms of unsafe behaviors. First, individual and environmental conditions that can lead to an unsafe behavior are identified through a holistic cognitive analysis and management conditions that affect such conditions are identified. Second, a system dynamics model for the causation of unsafe behaviors (SD-CUB) is developed to characterize the causal structure of the system. The SD-CUB model involves relationships among management, individuals, and environmental conditions that can eventually lead to workers’ unsafe behaviors. Third, a variety of model tests are conducted to build the confidence of the SD-CUB model. A five-week survey and observation on a bui...

Stochastic dynamic analysis of structures with random parameters continues to be an open question in the field of civil engineering. As a newly developed method, the probability density evolution method (PDEM) can provide the probability density function (PDF) of the dynamic responses of highly nonlinear structures. In this paper, a new method based on PDEM and the kriging surrogate model, named the K-PDEM, is proposed to study the stochastic response of a structure. Being an exact interpolation method, the Gaussian process regression or the so-called kriging method is capable of producing highly accurate results. Unlike the traditional PDEM numerical method whose numerical precision is strongly influenced by the number of representative points, the K-PDEM employs the kriging method at each instant to generate additional time histories. Then, the PDEM, which is capable of capturing the instantaneous PDF of a dynamic response and its evolution, is employed in nonlinear stochastic dynamic systems. Because of the decoupling properties of the K-PDEM, the numerical precision of the result is improved by the enrichment of the generalized density evolution equations without increasing the computation time. The result shows that the new method is capable of calculating the stochastic response of structures with efficiency and accuracy.

In order to gain deep insight into the underlying causation and identify correspondent management strategies in the prevention of construction workers’ unsafe behaviors, a conceptual system dynamics model was proposed. The paper mainly focuses on the confidence building of the model through model testing, which basically contains tests of model structure, model behavior and model’s policy implication. The conceptual model is quantified first before the formal process of model tests. Second, the paper applies semi-structured interviews for the structure-verification test to ensure the model’s appropriateness in depicting the structure of the real system. Third, tests of model behavior such as extreme-condition tests and behavior-reproduction tests are conducted, so as to demonstrate the plausibility of the patterns and behaviors the model generates. Fourth, model’s policy implication tests are presented to examine whether the model’s responses to predesigned policies are consistent with the real system. As a result, the model shows confidence in revealing the underlying causation of unsafe behaviors, which can be used as reference to the routine safety management in practice. Further suggestions for the application of the model as a tool of simulation in real construction projects are also given.

The preparation of polyurethane/poly(bismaleimide-urethane bismaleimide) [PU/P(BMI-UBMI)] IPNs were carried out in two steps. The two-network interaction and the morphology of PU/P(BMI-UBMI) IPNs were characterized by FTIR and TEM. The effect of the interpenetration of P(BMI-UBMI) and PU on the hydrogen bonds of N-H and the pyrolysis procedure of PU/P(BMI-UBMI) IPNs were investigated by DSC and TG. The results indicate that the interpenetration of P(BMI-UBMI) and PU reinforces the hydrogen bonding of N-H, and the incorporating of UBMI enhances the compatibility of the two networks, leading to ideal interpenetrating, which weakens the force constant of C-N-C in maleimide rings. The morphology of PU/P(BMI-UBMI) IPNs shows multiphase domains which have an obvious phase interface. The domains are connected to each other and the domain dimensions are far smaller than those of PU. The thermal weight loss shows obvious stages at different pyrolysis periods. The thermal stability of PU/P(BMI-UBMI) IPNs are much better than that of PU given the content and crosslink density of P(BMI-UBMI) in a certain range.

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To investigate the feasibility of using attenuated Salmonella typhi as an in vivo delivery vector for multidrug-resistance gene (MDR1) small interference RNA (siRNA) in a mouse model bearing human tongue squamous cell cancer. This technique may represent a novel and effective route for the in vivo administration of siRNA against malignant tumors.The cisplatin (DDP)-resistant human tongue squamous cell carcinoma cell line Tca8113/DDP, which highly expresses the MDR1 gene, was established by exposure to gradually increasing concentrations of cisplatin. A plasmid MDR1 siRNAwas constructed and transformed into attenuated Salmonella typhi strain SL7207. Tca8113/ DDP cells were infected with recombinant salmonella and expression of the MDR1 gene encoding P-glycoprotein (P-gp) product was detected. Tca8113/DDP tumor-bearing nude mice were established by inoculation by gavage administration of recombinant salmonella and were simultaneously injected intraperitoneally with cisplatin. Tumor growth was observed.Recombinant salmonella-bearing MDR1 siRNA expression plasmids can infect Tca8113/DDP cells in vitro and suppress P-gp expression and reverse DDP tolerance in Tca8113/DDP cells. Oral administration of recombinant salmonella in tumor-bearing nude mice can suppress tumor proliferation and enhance the therapeutic effect of DDP.Attenuated Salmonella typhi is expected to act as an in vivo targeting delivery vector for siRNA in tumor tissues.