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The study of the mechanical properties of natural gas hydrate sediments is an important part in the research of gas hydrate extraction technology. However, in the past, most of the researches focused on triaxial compression experiments, and few people studied the deformation in the process of depressurization mining. In order to study this problem, we have simulated the relationship between the axial deformation of natural gas hydrate sediments and aerogenesis in the process of depressurization. In this experiment, the in-situ formation and decompression decomposition of hydrate are simulated, and the overlying pressure of 13.5MPa is loaded, and the axial deformation of hydrate sediment is recorded. The conclusion is that, in the process of hydrate decompression decomposing, the strain increased with the amount of gas produced, the relationship between strain value and gas production percentage is a proportional function, and the proportional coefficient increases with the increase of hydrate saturation.

HMGB1 protein is a multifunctional cytokine involved in inflammatory reactions and is known to play a key role in tissue repair and fibrosis. However, the function of HMGB1 in fibrotic skin diseases, such as hypertrophic scar formation, remains unclear. In this study, HMGB1 was detected in the nuclei of epidermal cells in normal skin and had accumulated in the cytoplasm in hypertrophic scars. By establishing a keratinocyte-fibroblast co-culture and conditional medium treatment models, we found that a reduced hydration condition increased the expression and secretion of HMGB1 in keratinocytes, subsequently activating dermal fibroblasts. HMGB1 secreted from keratinocytes activated fibroblasts by promoting the nuclear import of MRTF-A, increased the nuclear accumulation of MRTF-A/SRF complexes and consequently enhanced α-smooth muscle actin promoter activation. Moreover, blockade of advanced glycation end products or Toll-like receptor 2/4 inhibited the fibroblast activation induced by HMGB1. Finally, local delivery of HMGB1 resulted in marked hypertrophic scar formation in rabbit hypertrophic scar models, while HMGB1 blockade exerted a clear anti-scarring effect. Our results indicate that high HMGB1 levels induced by a reduced hydration status play an important role in hypertrophic scar formation, strongly suggesting that HMGB1 is a novel target for preventing scarring.

Extraction of methane from hydrate-bearing sediment (HBS) has aroused increasing interest around the world. However, the decomposition of gas hydrate may cause significant sediment deformation, which is one of the main obstructions for the hydrate exploitation. To investigate the decomposition behaviors of methane hydrate in different sediments and study the sediment deformation during hydrate decomposition, two contrast experiments were carried out in a novel three-dimensional (3-D) high-pressure reactor with a quick-opening component. In this study, synthetic sandy sediment and natural silty clay sediment sampled from the Shenhu Area, South China Sea were used as the HBS. For hydrate in sandy sediment, the pressure-temperature (P-T) relationship is consistent with that of bulk hydrate. However, in silty clay sediment, the hydrate decomposition conditions shift into a higher pressure region than that in sandy sediment, which is mainly due to the small pore particle size and the presence of salinity. In addition, hydrate decomposition conditions in silty clay sediment also vary at different positions in the reactor because of the effects of salinity, organics, minerals and the uneven distribution of the pores and pore particles. Hence, it is considered that there is a variable equilibrium for the methane hydrate deposits in silty clay sediment. Further, Radial Shrinkage Effect of Hydrate Decomposition (RASHEHD) was observed in both experiments. It is possibly a combined consequence of gas seepage and the cementation effect of hydrate.

This paper aims to perform stochastic motion analysis and the system probability estimation of exceedance in motion of a jack-up unit in wet tow mode to assess its safety in terms of its translational and rotational motions. When a jack-up unit is afloat and towed in seaways, it is important to determine the extreme motion response for the stability of the platform and to ensure the safety of equipment on the deck. This paper discusses the hydrodynamic characteristics and motion behavior of a jack-up unit with mat at a certain towing speed in various sea states with significant wave height ranging from 2 m to 5 m and wave directions ranging from 0° to 90°. The significant motion responses, such as heave, roll and pitch, are estimated by the frequency domain method. The probability of exceedance of the motion responses of the jack-up in random seas is estimated by means of system reliability analysis, considering wave overtopping, instability for roll, instability for pitch, and their series system. In order to efficiently determine the limit state exceedance probabilities due to time varying random variables, the Monte Carlo simulation technique and the subset simulation method have been employed in this study. The results from deterministic analysis and probabilistic analysis are comparably discussed, and the estimation of the extreme value statistics of motion responses in various sea states is provided. The approach developed in this paper can be applied to predict an unsafe condition of the jack-up and other platforms during wet towing in seaways supporting the officer׳s decisions on the action taken if excessive responses are foreseen for the present course and speed.

Detailed finite element analysis has been carried out for different bollard supporting structures by ANSYS software. From the analysis results, it can be seen that the bollard supporting structures are of adequate strength to take the design load transferred from the mooring rope during operation considering the requirement on strength criteria from IACS, and strength check is performed in accordance with the updated relevant ABS standard. Finally, a comparison of these different bollard supporting structures is made to find out their own advantages from safety and other aspects.

Pendulous Installation Method is fit for the installation of subsea facilities in Liwan 3-1 field. In this paper, non-liner coupling time domain analyses of the hull, the sling and the manifold are conducted, combined with an investigation into the critical factors affecting the lowering process, to improve the controllability of the lowering process and to make proposals about Liwan project.

The antioxidant differences between two flavonoid extracts from fruiting body and fermentation broth of Phellinus igniarius were determined, and the effects of flavonoid addition on the sensory characteristics of sturgeon caviar were investigated. Both extracts exhibited moderate antioxidant activity with EC50 values of 4.98 and 2.39 mg/mL, the extract of fermentation broth exhibiting higher antioxidant efficiency. Flavonoids were added at 0.01% and 0.02% to sturgeon caviars, which were then stored at 4 or 20 °C for 12 days. Peroxide values (meq/kg) were determined after regular intervals. The 0.02% level of flavonoids from fermentation broth of P. igniarius had stronger antioxidant effect than vitamin C, very close to that of butylated hydroxyanisole (BHA). Flavonoid addition improved the sensory profile of caviar, and the flavonoid extract from the fermentation broth had a more desirable effect on flavour and aroma than that from fruiting bodies.

Fishing activities as well as other third-party factors can have great impact on the safety of subsea pipelines. Through an investigation into fishing activities in different sea areas in China, combined with theoretical and modeling calculation of the actual influence of the impacting trawl board and anchor on pipelines, a recommended under bed solution of subsea pipeline was worked out. The solution can provide reference in rule-making involving the burial depth of subsea pipelines.

Rice straw was pretreated with alkaline to improve degradation by Coprinus cinereus. After straw soaked in 5% NaOH for 24h, straw biodegradation conditions include nitrogen source concentration, moisture content, pH which were the main influence factors were studied. The results showed the optimum nitrogen source concentration was 3%, moisture content was 65% and pH was 6 for 15d fermentation. A theoretical maximum cellulose biodegradation of 34.4% was obtained when straw chips were under the fermentation condition of nitrogen source concentration (ammonium nitrate)4.47%(w/w), moisture content 67.4%(w/w), pH 6.37 fermented at 28°Cfor 15d by RSA Experiment.

In this study, Box-Behnken design (BBD) and response surface analysis (RSA) methodology were employed to plan experiments and optimize the NaOH pretreatment of rice straw. Experimental results showed that concentration of NaOH (CS), treatment time (TT) and ratio of rice straw with NaOH (RS) were main factors governing the biogasification of rice straw. The polynomial equation describing the biogasification as a simultaneous function of the CS, TT and RS was confirmed. The FTIR analysis and SEM images of straws further confirmed that NaOH could disrupt the silicified waxy surface, break down the lignin-hemicellulose complex and partially remove silicon and lignin from the pretreated rice straw.

To assess the effect of intensive statins therapy on the outcome of small-diameter vascular prosthesis, we investigated whether atorvastatin treatment (30 mg/d) could accelerate the re-endothelialization process and improve the patency rate in a canine infrarenal abdominal aorta-expanded polytetrafluoroethylene (ePTFE) bypass model. Furthermore, we also evaluated the effect of atorvastatin on the migratory and adherent capacity of circulating endothelial progenitor cells (EPCs) in vitro. Improved patency was confirmed by Doppler sonography and arteriography. Histological and scanning electron microscopy illustrated enhanced re-endothelialization process. Treatment with atorvastatin enhanced the circulating pool of EPCs with fortified migratory and adherent capacity. Reverse transcriptase—polymerase chain reaction (RT-PCR) analysis showed that atorvastatin treatment increased endothelial nitric oxide synthase (eNOS) and kinase insert domain receptor (KDR) messenger RNA (mRNA) expression in cultured EPCs and neointima. In conclusion, intensive statin therapy could be considered a favorable option to improve small-diameter vascular graft patency.

Recruitment and entrapment of bone marrow-derived endothelial progenitor cells (EPCs) is important in vascular endothelial growth factor (VEGF)-induced angiogenesis. EPC mobilization and differentiation are modulated by stromal-derived factor-1alpha (SDF-1alpha/CXCL12), another important chemokine. In this study, we investigated the hypothesis that SDF-1alpha and VEGF might act synergistically on EPC-mediated vasculogenesis.EPCs were isolated and cultured from human peripheral blood, then transduced with retroviral vectors pBabe containing human VEGF(165) complimentary DNA (Td/V-EPCs) and pBabe wild-type (Td/p-EPCs). EPC migration activity was investigated with a modified Boyden chamber assay. EPC apoptosis induced by serum starvation was studied by annexin V assays. The combined effect of local administration of SDF-1alpha and Td/V-EPC transplantation on neovascularization was investigated in a murine model of hind limb ischemia.Over-expression of hVEGF(165) increased SDF-1alpha-mediated EPC migration. SDF-1alpha-mediated migration was significantly increased when EPCs were modified with VEGF (Td/V-EPCs) vs when VEGF was not present (Td/p-EPCs) or when VEGF alone was present (Td/V-EPCs; 196.8 +/- 15.2, 81.2 +/- 9.8, and 67.4 +/- 7.4/mm(2), respectively P.001). SDF-1alpha combined with VEGF reduced serum starvation-induced apoptosis of EPCs more than SDF-1alpha or VEGF alone (P.001). To determine the effect of this combination in vivo, SDF-1alpha was locally injected alone into the ischemic hind limb muscle of nude mice or combined with systemically injected Td/V-EPCs. The SDF-1alpha plus VEGF group showed significantly increased local accumulation of EPCs, blood-flow recovery, and capillary density compared with the other groups. The ratio of ischemic/normal blood flow in Td/V-EPCs plus SDF-1alpha group was significantly higher (P.01), as was capillary density (capillaries/mm(2)), an index of neovascularization (Td/V-EPCs plus SDF-1alpha group, 863 +/- 31; no treatment, 395 +/-13; SDF-1alpha, 520 +/- 29; Td/p-EPCs, 448 +/- 28; Td/p-EPCs plus SDF-1alpha, 620 +/- 29; Td/V-EPCs, 570 +/- 30; P.01). To investigate a possible mechanistic basis, we showed that VEGF up-regulated the receptor for SDF-1alpha, CXCR4, on EPCs in vitro.The combination of SDF-1alpha and VEGF greatly increases EPC-mediated angiogenesis. The use VEGF and SDF-1alpha together, rather than alone, will be a novel and efficient angiogenesis strategy to provide therapeutic neovascularization.

To solve the problem of resource scheduling in project group management, which is a crying problem in offshore project management, the ant colony optimization (ACO) algorithm was introduced. First, the similarities between resource dynamic scheduling problem and ant's food-seeking were analyzed and the meta-information was defined. Second, the dynamic scheduling model was proposed. Then, engineering practice in offshore project group resource scheduling showed that the resources can be allocated timely, dynamically and rationally by using this algorithm. The method can also be introduced into other related spheres. This study will give rise to project group management.

Skin-derived precursors (SKPs), which are located at skin's dermis, display multi-lineage potential and can produce both neural and mesodermal progeny in vitro. SKPs are considered to take part in dermal reconstruction and may be an important source of fibroblast during wound repairing. To explore the possibility of differentiation of SKPs into fibroblasts, the 3(rd) passage SKPs were treated with 0, 20, 40, 100, or 500 ng/ml human recombinant connective tissue growth factor (CTGF) for 48 h or treated with 100 ng/ml CTGF for 0, 24, 48, 72, or 96 h. Subsequently, a series of methods were to be used to observe cells immunocytochemistry changes under fluorescence microscope, to validate the mRNA expression change of collagen I, collagen III, fibroblast-specific protein 1 (FSP-1) and alpha smooth muscle actin (α-SMA) by quantitative real-time reverse transcriptase polymerase chain reaction (QRT-PCR), to analyze the expression of collagen I and collagen III protein by Enzyme-linked immunosorbent assay (ELISA), to semiquantitatively measure the expression of FSP-1 and α-SMA by western-blot. After differentiation, cells showed that positively staining for collagen I, collagen III, α-SMA, and FSP-1, which are markers for fibroblasts, but negative expression for neural precursors. The effects of CTGF on collagen I, collagen III, FSP-1 and α-SMA in SKPs were detected both on the transcriptional and posttranscriptional levels. These findings indicate that SKPs can be induced to differentiate into fibroblast-like cells with CTGF treatment that may be a key source of fibroblast in wound healing.

[1] The lateral distributions of depth-averaged apparent shear stress, depth mean velocity, and diffusion coefficients are essential in certain quantitative analysis for sediment transport and environmental studies. An analytical method for the computation of these parameters is presented. A mathematical relationship between these parameters, based on the concept of surplus energy transport through a minimum relative distance developed by Yang and Lim [1997], is established, the depth-averaged apparent shear stress is determined from the boundary shear stress, depth mean velocity is obtained by considering the influence of nonuniform shear velocity and the free surface in 3-D channels, and the diffusion coefficients are linked to the depth-averaged apparent shear and velocity. The theoretical formulations for the distributions of depth-averaged apparent shear stresses, depth mean velocity and diffusion coefficients in trapezoidal and compound channels are presented. Comparisons between the theoretical and the measured lateral distributions of the depth-averaged apparent shear stresses and the depth mean velocities are also presented, and a reasonable agreement is achieved.

AIM: To compare and evaluate the appropriate prognostic indicators of lymph node basic staging in gastric cancer patients who underwent radical resection. METHODS: A total of 1042 gastric cancer patients who underwent radical resection and D2 lymphadenectomy were staged using the 6th and 7th edition International Union Against Cancer (UICC) N staging methods and the metastatic lymph node ratio (MLNR) staging. Homogeneity, discriminatory ability, and gradient monotonicity of the various staging methods were compared using linear trend χ2, likelihood ratio χ2 statistics, and Akaike information criterion (AIC) calculations. The area under the curve (AUC) was calculated to compare the predictive ability of the aforementioned three staging methods. RESULTS: Optimal cut-points of the MLNR were calculated as MLNR0 (0), MLNR1 (0.01-0.30), MLNR2 (0.31-0.50), and MLNR3 (0.51-1.00). In univariate, multivariate, and stratified analyses, MLNR staging was superior to the 6th and 7th edition UICC N staging methods. MLNR staging had a higher AUC, higher linear trend and likelihood ratio χ2 scores and lower AIC values than the other two staging methods. CONCLUSION: MLNR staging predicts survival after gastric cancer more precisely than the 6th and 7th edition UICC N classifications and should be considered as an alternative to current pathological N staging.