The Pro12Ala Polymorphism of PPAR- γ

Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a ligand-binding nuclear receptor, and its activation plays a prominent role in regulating the inflammatory response. Therefore, PPAR-γ has been suggested as a candidate gene for sepsis. In the present study, we investigated the association between the Pro12Ala polymorphism of PPAR-γ and sepsis in a Han Chinese population. A total of 308 patients with sepsis and 345 healthy controls were enrolled in this study. Genotyping was performed using the polymerase chain reaction-ligation detection reaction (PCR-LDR) method. No significant differences were detected in the allele and genotype distributions of the PPAR-γ Pro12Ala SNP between septic patients and controls (P=0.622 for genotype; P=0.629 for allele). However, stratification by subtypes (sepsis, septic shock, and severe sepsis) revealed a statistically significant difference in the frequency of the Ala allele and Ala-carrier genotype between the patients with the sepsis subtype and the healthy controls (P=0.014 for allele and P=0.012, for genotype). Moreover, significant differences were found in the frequency of the Ala allele and genotype between the sepsis survivors and nonsurvivors (all P=0.002). In the survivors, the PPAR-γ Pro12Ala genotype was significantly associated with decreased disease severity and recovery time (all P<0.001). Thus, genetic polymorphism is thought to play a role in the development and outcome of sepsis

A New Technology Combined Corrosion inhibition and water shutoff in Oil Well

In order to solve the problem of high water cut and serious corrosion in oil well, a new technology combined the corrosion inhibition and water shutoff in oil well is proposed and developed in this paper. In this technology, corrosion inhibitor solution is first injected into the oil well, then followed by selective water shutoff agent, which mothballs the corrosion inhibitor in the high permeability zone. As the oil well is resumed to produce, the succeeding water (injected water or edge water) carries corrosion inhibitor to gradually produce along medium and low permeability zone in order to achieve the multi-purpose of inhibiting the corrosion of pipe string, decreasing the water cut and increasing oil production. The optimized corrosion inhibitor and water shutoff agent were screened out for the reservoir condition before field application. The mechanisms of the new method were studied using physical simulation experiments. This technology is carried out in one well of Shengli oilfield and gets good field effect. Copyright 2010, Society of Petroleum Engineers.EI

A fault tree-based approach for aviation risk analysis considering mental workload overload

Many lives and aircrafts have been lost due to human errors associated with mental workload overload (MWLOL). Human errors are successfully considered in existing Fault Tree Analysis (FTA) methods. However, MWLOL is considered through Performance Shaping Factors indirectly and its information is hidden in FT construction, which is not conducive to analyze the root causes of human errors and risks. To overcome this difficulty, we develop a risk analysis method where Multiple Resources Model (MRM) is incorporated into FTA methods. MRM analyzes mental workload by estimating the resources used during performing concurrent tasks, probably including abnormal situation handling tasks introduced by basic events in FT. Such basic events may cause MWLOL and then trigger corresponding human error events. A MWLOL gate is proposed to describe MWLOL explicitly and add these new relationships to traditional FT. This new method extends previous FTA methods and provides a more in-depth risk analysis. An accident, a helicopter crash in Maryland, is analyzed by the proposed method

Shear Strength Prediction for SFRC Shear Wall with CFST Columns by Softened Strut and Tie Model

The steel fiber reinforced concrete (SFRC) shear wall with concrete filled steel tube (CFST) columns is an innovative composite structure. In order to calculate the shear strength of SFRC shear wall with CFST columns, the softened strut and tie model (SSTM) of SFRC shear wall with CFST columns was proposed based on the analysis of shear mechanism of SFRC shear wall with CFST columns. The SSTM was composed of diagonal, horizontal, and vertical mechanisms, in which the contributions of concrete, reinforcement, and steel fiber to the shear strength of SFRC web of shear wall were identified. The shear capacities of 24 shear walls were calculated and compared with the available test results, and reasonable agreement was obtained. The results also showed that the steel fibers distributed randomly in concrete could be treated as longitudinal and transverse reinforcement in the shear strength analysis of SFRC web, and the SSTM was reasonable and useful to analyze and predict the shear strength of SFRC shear wall with CFST columns