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A dual-chamber air spring is an important vibration absorber. The shape and number of damping orifices directly influence the damping characteristics of dual-chamber air springs. The study investigates the application of damping characteristics of gas-liquid coupling dual-chamber air springs to mitigate the motion of a marine floating platform. An experimental method is used to analyze the influence of changes in the orifice number and shape on the damping characteristics of dual-chamber air springs given the same opening area. To analyze the effect of various orifice shapes, the study adopts a non-dimensional number to measure the image complexity, namely area/perimeter2 ratio. Additionally, two non-dimensional numbers are considered simultaneously, namely the orifice number and tightness factor, and the influence of changes in the orifice number and orifice position layout on damping characteristics of circular and square orifices is investigated, given the same opening area. The damping cloud map and a formula to calculate the damping for the gas-liquid coupling dual-chamber air springs are obtained by analyzing the experimental data. The proposed formula can be used to quickly calculate the damping coefficients of the dual-chamber air springs when the number and position layout of the orifices are known. [ABSTRACT FROM AUTHOR]

Deep-sea floating platforms are one of the most important large structures for ocean energy exploitation. A new energy-absorbing device named S-shaped Tuned Liquid Column Damper (TLCD) has been invented for the suppression of the horizontal motion and vertical in-plane rotation of a deep-sea floating platform. A conventional tuned liquid column damper has a U-shaped water tunnel to absorb the excessive energy of the main structure. The application of U-shaped dampers in deep-sea floating platforms is difficult due to the restriction of a large horizontal length. A novel S-shaped damper is proposed to retain the same amount of liquid using a shorter S-shaped tunnel. Theoretical and experimental works are conducted and prove that an S-shaped damper needs less than half the horizontal length to provide the same suppression as a U-shaped damper. A coupling calculation model is proposed and followed by the sensitivity analysis. The study demonstrates the applicability of the novel S-shaped damper for the motion suppression in deep-sea floating platforms. [ABSTRACT FROM AUTHOR]

Background: Continuation maintenance treatment with pemetrexed is approved by current clinical guidelines as a category 2A recommendation after induction therapy with cisplatin and pemetrexed chemotherapy (CP strategy) for patients with advanced nonsquamous non-small-cell lung cancer (NSCLC). However, the cost-effectiveness of the treatment remains unclear. Objective: We completed a trial-based assessment, from the perspective of the Chinese health care system, of the cost-effectiveness of maintenance pemetrexed treatment after a CP strategy for patients with advanced nonsquamous NSCLC. Methods: A Markov model was developed to estimate costs and benefits. It was based on a clinical trial that compared continuation maintenance pemetrexed therapy plus best supportive care (BSC) versus placebo plus BSC after a CP strategy for advanced nonsquamous NSCLC. Sensitivity analyses were conducted to assess the stability of the model. Results: The model base case analysis suggested that continuation maintenance pemetrexed therapy after a CP strategy would increase benefits in a 1-, 2-, 5-, or 10-year time horizon, with incremental costs of $183,589.06, $126,353.16, $124,766.68, and $124,793.12 per quality- adjusted life-year gained, respectively. The most sensitive influential variable in the cost-effectiveness analysis was the utility of the progression-free survival state, followed by proportion of patients with postdiscontinuation therapy in both arms, proportion of BSC costs for PFS versus progressed survival state, and cost of pemetrexed. Probabilistic sensitivity analysis indicated that the cost-effective probability of adding continuation maintenance pemetrexed therapy to BSC was zero. Oneway and probabilistic sensitivity analyses revealed that the Markov model was robust. Conclusions: Continuation maintenance of pemetrexed after a CP strategy for patients with advanced nonsquamous NSCLC is not cost-effective based on a recent clinical trial. Decreasing the price or adjusting the dosage of pemetrexed may be a better option for meeting the treatment demands of Chinese patients. [ABSTRACT FROM AUTHOR]

Background: Because of the potentially significant economic burden of healthcare costs associated with many diseases, it is critical that regulatory and medical insurance organisations collect and utilise data on the cost-effectiveness of care provision to make rational policy decisions. However, little is known about healthcare costs in China. Methodology/Principal Findings: Based on health expenditure data for 253 cases of advanced non-small cell lung cancer (NSCLC) registered at the Second Xiangya Hospital of Central South University in China between 2006 and 2010, the cost of care provision was analysed. The monthly and aggregate annual medical costs were estimated for patients who were in either a progression-free state (PFS) or a disease-progression state (DPS). Monthly healthcare costs accumulated during the terminal 3 months were collected separately. The mean cost of treatment for PFS and DPS patients over one year was approximately US$11,566 and $14,519, respectively. The monthly costs for all patients were higher initially than in the subsequent months (PFS: $2,490; DPS: $2,503). For PFS patients, healthcare expenditures stabilised after the 7th month, with a mean monthly medical expenditure of $82.49. For DPS patients, expenditures stabilised after the 9th month, and the mean expenditure during the 9th month was $307.9. Medical care costs in the three successive months prior to death were $3,754, $5,829 and $7,372, respectively. Conclusions/Significance: The economic evaluation of health care technologies is becoming ever more important in China, especially in disease areas for which new and expensive therapies are being introduced on a regular basis. This is first paper to present empirically estimated China-specific costs associated with the treatment of NSCLC. The cost estimates are presented in a format that is specifically intended to inform cost-effectiveness analyses of treatments for NSCLC, and hence, contribute to the more efficient allocation of limited healthcare resources in China. [ABSTRACT FROM AUTHOR]

Chemical model reactions were carried out to investigate the effect of a citrus flavonoid, naringenin, on the formation of acrylamide under mild heating conditions. Results showed that naringenin significantly and dose dependently inhibited the formation of acrylamide (20−50% relative to the control), although not in a linear manner. Moreover, the presence of naringenin in acrylamide-producing models effectively reduced the extent of browning. Careful comparison of the HPLC chromatograms of samples from the chemical model reactions revealed that naringenin likely reacted with Maillard intermediates, giving rise to new derivatives. Subsequent LC-MS analyses suggested that the proposed derivatives have a predicted molecular mass of 341 Da. Eventually, two derivatives were purified and characterized with LC-MS/MS and NMR spectroscopy as 8-C-(E-propenamide)naringenin and 6-C-(E-propenamide)naringenin, respectively. In other words, naringenin, a rather weak antioxidant, strongly inhibited acrylamide formation probably by directly reacting with acrylamide precursors, thus diverting them from the pathways that lead to acrylamide formation. [ABSTRACT FROM AUTHOR]

For low permeability bottom water reservoir, controlling the vertical propagation of fracture is the key to fracturing treatment. At present, using plugging agent to form an artificial barrier has become the mainstream technology. However, it lacks a quantitative model to describe the influence of fracturing treatment parameters on fracturing effect directly. Authors intended to develop an automatic optimisation tool to provide fracturing treatment parameters for bottom water reservoirs fracturing. First, a new model has been proposed based on the principle of reservoir numerical simulation and considering the characteristics with plugging agent layer in the fracture. The simulation results show that moderate plugging is good for oil production. Second, a genetic algorithm as an optimisation technique is used to obtain a fracturing design that maximises the net present value. Finally, the proposed method has been applied in Luliang oilfield in China. 6 tested wells achieved a significant increase of oil production and decrease of water cut than the 3 offset ones. [ABSTRACT FROM AUTHOR]

It has previously been demonstrated that curcumin possesses a hypocholesterolemic effect and potentiates numerous pharmacological effects of curcumin, however, the mechanisms underlying this hypocholesterolemic effect and the interaction between curcumin and piperine remain to be elucidated. In the present study, male Sprague-Dawley rats were fed on a high-fat diet (HFD) to establish a hyperlipidemia (HLP) model. Co-administration of curcumin plus piperine was found to decrease the levels of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol in the serum and liver, as well as increase the levels of fecal TC, TG and total bile acid, compared with administration of curcumin alone. Curcumin plus piperine also markedly increased the levels of high-density lipoprotein cholesterol. Furthermore, compared with administration of curcumin alone, administration of curcumin plus piperine resulted in a significant upregulation of the activity and gene expression of apolipoprotein AI (ApoAI), lecithin cholesterol acyltransferase (LCAT), cholesterol 7a-hydroxylase (CYP7A1) and low-density lipoprotein receptor (LDLR). In conclusion, these results indicated that co-administration of curcumin plus piperine potentiates the hypocholesterolemic effects of curcumin by increasing the activity and gene expression of ApoAI, CYP7A1, LCAT and LDLR, providing a promising combination for the treatment of HLP. [ABSTRACT FROM AUTHOR]

Background: Postoperative adjuvant chemotherapy with capecitabine and oxaliplatin was first recommended for resectable gastric cancer patients in the 2011 Chinese National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology: Gastric Cancer, but the economic influence of this therapy in China is unknown. Objective: The aim of the present study was to determine the cost-effectiveness of adjuvant chemotherapy with capecitabine and oxaliplatin after a gastrectomy with extended (D2) lymph-node dissection, compared with a D2 gastrectomy alone, for patients with stage II-IIIB gastric cancer. Methods: On the basis of data from the CLASSIC trial, a Markov model was created to determine economic and clinical data for patients in the chemotherapy and surgery group (CSG) and the surgery-only group (SOG). The costs, presented in 2010 US dollars and estimated from the perspective of the Chinese health-care system, were obtained from the published literature and the local health system. The utilities were based on published literature. Costs, life years (LYs), quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICER) were estimated. A lifetime horizon and a 3 % annual discount rate were used. One-way and probabilistic sensitivity analyses were performed. Results: For the base case, the CSG compared with SOG would increase LYs and QALYs in a 3-, 5-, 10- or 30-year time horizon (except the QALYs at 3 or 5 years). In the short run (such as in 3 or 5 years), the medical costs would increase owing to adjuvant chemotherapy of capecitabine plus oxaliplatin after D2 gastrectomy, but in the long run the costs would decline. The ICERs suggested that the SOG was dominant at 3 or 5 years and the CSG was dominant at 10 or 30 years. The one-way sensitivity analysis showed that the utility of disease-free survival for 1-10 years for the SOG and the cost of oxaliplatin were the most influential parameters. The probabilistic sensitivity analysis predicted a 98.6 % likelihood that the ICER for the CSG would be less than US$13,527/QALY (three times the per capita gross domestic product of China). Conclusion: For patients in China with resectable disease, our results suggest that adjuvant chemotherapy with capecitabine plus oxaliplatin after a D2 gastrectomy is cost-saving and dominant in the long run on the basis of a current clinical trial, compared with treatment with a D2 gastrectomy alone. [ABSTRACT FROM AUTHOR]

Allergen-specific immunotherapy for house dust mite allergy is effective, but there are no validated biomarkers reflecting or predicting the clinical efficacy. We aimed to investigate the relationship between clinical outcomes and functional responses of allergen-specific IgG4 (sIgG4) and specific IgE (sIgE) during Dermatophagoides pteronyssinus s.c. allergen immunotherapy (SCIT) in allergic rhinitis and/or asthma patients. Combined symptom medication scores (SMS), D. pteronyssinus--sIgG4 levels, D. pteronyssinus--sIgE levels, and the serum inhibitory capacity against D. pteronyssinus--sIgE facilitated allergen binding to B cells (IgE-FAB) were determined during the updosing (week 0, 4, 12, and 16) and maintenance (week 52, 104, and 156) phase of SCIT. We found that SCIT patients had a significant improvement in SMS from week 52 to 156 compared with medication-treated control subjects (p < 0.05). Levels of D. pteronyssinus--sIgG4 in SCIT patients showed a significant increase from week 12 to 156 (p < 0.05). Serum obtained from SCIT patients significantly inhibited D. pteronyssinus--sIgE binding to B cells after 16 wk (p < 0.01). Significantly lower levels of D. pteronyssinus--sIgE were observed in SCIT patients after 52 wk (p <0.05).A significant relationship was demonstrated between SMS and IgE-FAB or D. pteronyssinus--sIgG4 during the maintenance phase according to linear regression analysis. In conclusion, D. pteronyssinus--sIgG4 level and D. pteronyssinus IgE-FAB are associated with clinical efficacy in the maintenance phase rather than the updosing phase of SCIT. Immunologic tolerance can be induced with SCIT when maintenance phase is achieved. [ABSTRACT FROM AUTHOR]

Uniaxial compression test of cement asphalt (CA) mortar specimens, due to drying and wetting cycle of 0, 2, 4 and 8 times, is carried out by using the electronic universal test machine, with the strain rate ranging from 1 x 10-5 s-1 to 1 x 10-2 s-1. The effects of strain rate and drying and wetting cycle time on the compressive strength, elasticity modulus, and stress-strain full curve are investigated. Experimental results show that the strain-stress full curve of CA mortar is affected obviously by strain rate and drying and wetting cycle time. The compressive strength and elasticity modulus increase with the strain rate under the same drying and wetting cycle time. The compressive strength and elasticity modulus decrease with the increase of drying and wetting cycle time in the same strain rate. The lower the strain rate is, the greater the compressive strength and elasticity modulus of CA mortar decrease. When the strain rate is 1 x 10-5 s-1 and drying and wetting cycle time is 8, the largest reduction of average compressive strength of CA mortar is 40.48%, and the largest reduction of elasticity modulus of CA mortar is 35.51%, and the influence of drying and wetting cycle on the compressive strength of CA mortar is greater than its influence on the elasticity modulus. [ABSTRACT FROM AUTHOR]

The article demonstrates a new type of nanoporous polymer capable of efficient water desalination and nanofiltration (NF). Based on a cross-linked Q1-phase lyotropic liquid crystal (LLC) assembly, the authors note that the material has an effective pore size of 0.75 nanometer and is capable of high salt rejection, with a water permeability similar to that of commercial reverse osmosis (RO) membranes in dead-end filtration. Results of the study and its implications are presented and discussed.