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Background: Arteriovenous fistulas (AVFs) and grafts (AVGs) have been associated with improved clinical outcomes in children and adults with end-stage renal disease (ESRD) on maintenance hemodialysis (HD) therapy, but use of vascular catheters is high. Identifying the reasons for the high prevalence of vascular catheters in children on HD therapy is necessary to assess whether targeted interventions may increase the prevalence of AVFs/AVGs.Study Design: Retrospective cohort study.Setting& Participants: Children younger than 18 years on HD therapy in the 2001 to 2003 ESRD Clinical Performance Measures (CPM) Projects followed up in the US Renal Data System transplant files through December 31, 2004.Predictor: Vascular access type and reasons for use of a vascular catheter.Outcomes& Measurements: Demographic/clinical characteristics, including the reason provided for use of a vascular catheter, and the association of type of vascular access and (1) patient size and (2) time to kidney transplantation.Results: Of 1,284 prevalent pediatric CPM patients examined, 529 (41%) had an AVF/AVG and 755 (59%) had a vascular catheter. Of 755 children with a catheter, "small body size" was a commonly listed reason (N = 142); 49% of these children weighed 20 kg or more. Of 53 patients with catheters described as having an "AVF/AVG maturing" and present in the consecutive ESRD CPM project year, 64% had a functioning AVF/AVG the following year. For those with "transplantation scheduled" listed as a reason for a vascular catheter (N = 83), 69% underwent transplantation within 1 year, and median time to transplantation was 115 days. Of all children with vascular catheters (N = 755), 32.2% underwent transplantation within 1 year, and median time to transplantation was 264 days compared with 21.7% and 347 days for those with AVFs/AVGs, respectively (N = 529). Of the 445 incident children in this cohort, 89% had a vascular catheter at dialysis therapy initiation.Limitations: Because of study design, only associations can be described.Conclusions: Vascular catheter use in children on HD therapy is high. This is partially explained by expeditious transplantation and technical barriers to AVF/AVG placement in small children; however, only one-third of patients with a vascular catheter underwent transplantation within 1 year. Interventions to decrease vascular catheter use in this population may be necessary. [ABSTRACT FROM AUTHOR]

This study used the manufacturing process in the petrochemical industries as an example and developed a dedicated maintenance programme and executive information system (EIS) for this industry. The software for EIS was established on a CMMS platform, with logical and extractive analysis used to store the information in a KPI databank. The system developed can provide plant managers and engineers with a complete summary of information and keep them updated regarding the present status of their maintenance efforts. The objective of this study was to establish a management system for maintaining knowledge in the petrochemical industries, such as the management of standard operating procedures (SOPs), historical records and the analysis of data for the facility. To design the software, a review of petrochemical facility was purposed to enhance the maintenance efforts and facilitate the decision-making process. The main functions of the system include asset reliability analysis, failure analysis and maintenance benefit cost analysis. For the petrochemical industry, the impact of safety and environment caused by equipment malfunction is more substantial than that of other industries. If executives can manage essential points effectively and make decisions according to a key performance index, risks to safety and environment, which result from equipment malfunction, can be decreased and safety can be enhanced for petrochemical refineries. [ABSTRACT FROM AUTHOR]

Abstract: A wavelength-multiplexed, fiber-optic-based, line-of-sight, diode-laser absorption sensor is developed for crank-angle-resolved measurements of temperature and water concentration in a homogeneous-charge-compression-ignition (HCCI) engine. An initial demonstration of its use on two optical HCCI engines at Sandia National Laboratories is reported. The measurements encompassed both motored- and fired-engine operation for temperatures between 300 and 1700K and pressures between 1 and 55bar. A spectroscopic line selection process identifies the most appropriate water absorption linepair for thermometry under these conditions. Key solutions to suppress crank-angle-dependent noise in the transmitted laser signals are reported, including careful spectroscopic design and optical engineering to accommodate beam-steering, engine vibration and polarization-related interference. Data obtained through this sensor can provide critical engine characteristics such as combustion efficiency, peak combustion temperature, and autoignition temperature. The flexibility of the wavelength-multiplexed architecture allows the straightforward addition of other wavelengths to potentially enable the simultaneous measurement of other important engine parameters such as temperature non-uniformity, and fuel, CO, and CO2 concentrations. [Copyright &y& Elsevier]

Abstract: Evolution of a universe with homogeneous extra dimensions is studied with the benefit of a well-chosen parameter space that provides a systematic, useful, and convenient way for analysis. In this model we find a natural evolution pattern that entails not only stable extra dimensions in the radiation-dominated era, thereby preserving essential predictions in the standard cosmology, but also the present accelerating expansion while satisfying the limit on the variation of Newtonian gravitational constant. In this natural evolution pattern the extra dimensions tend to be stabilized automatically without resorting to artificial mechanisms in both the radiation-dominated and the matter-dominated era, as a wonderful feature for building models with extra dimensions. In addition, the naturalness of this evolution pattern that guarantees the late-time accelerating expansion of a matter-dominated universe presents a solution to the coincidence problem: why the accelerating phase starts at the present epoch. The feasibility of this evolution pattern for describing our universe is discussed. [Copyright &y& Elsevier]

The change in the physical and chemical properties of a LaC 2 -2C disk (Ф: 50 mm, thickness: 1.3 mm), was investigated after a high temperature integrity tests (HTITs). The tests were conducted as precedent research to UC x , which is as an isotope separation on-line (ISOL) target material. The HTITs were performed under 10−6 Torr at three different temperatures (1600 °C, 1800 °C and 2000 °C) and two exposure times (24 h and 48 h). The microstructure and composition of the disks were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The density of the disks were also measured to calculate the porosity. The test results indicate that the LaC 2 -2C target disk satisfies the requirements for use as an ISOL target. [ABSTRACT FROM AUTHOR]