Correction of anaemia in haemodialysis patients with recombinant human erythropoietin

The binding and degradation of radiolabelled immune complexes by cultured rat glomerular mesangial cells were measured and compared with the binding and degradation by thioglycollate-elicited rat peritoneal macrophages. Mesangial cells are generally considered to be a modified pericyte with smooth muscle-like properties, but they were able to bind and degrade soluble immune complexes at rates comparable to those of the macrophages. In a second study, the ability of cultured mesangial cells to bind and degrade immune complexes of varying molecular weight was assessed. Very large, insoluble complexes were found to bind to mesangial cells more avidly than small soluble complexes, but unlike the small complexes, the large complexes did not appear to undergo degradation. These findings support a role for the intrinsic mesangial cell in the elimination of small soluble immune complexes as they arrive in the glomerulus. They also provide a possible explanation for the paradox that large immune complexes--i.e., electron-dense deposits--can persist in the mesangium next to the intrinsic mesangial cells without being rapidly destroyed.     

A phase reconstruction algorithm from bispectrum [seismicreflection data]

A computationally efficient procedure for the reconstruction of the impulse response of a (minimum- or nonminimum-phase) linear time-invariant system from its bispectrum is presented. This method is based on computing cepstrum of the impulse response sequence from the ω₁=ω₂ slice of the bispectrum. The algorithm can be implemented by using only the one-dimensional fast Fourier transform algorithm     

CPT-Based Probabilistic and Deterministic Assessment of In Situ Seismic Soil Liquefaction Potential

This paper presents a complete methodology for both probabilistic and deterministic assessment of seismic soil liquefaction triggering potential based on the cone penetration test (CPT). A comprehensive worldwide set of CPT-based liquefaction field case histories were compiled and back analyzed, and the data then used to develop probabilistic triggering correlations. Issues investigated in this study include improved normalization of CPT resistance measurements for the influence of effective overburden stress, and adjustment to CPT tip resistance for the potential influence of “thin” liquefiable layers. The effects of soil type and soil character (i.e., “fines” adjustment) for the new correlations are based on a combination of CPT tip and sleeve resistance. To quantify probability for performance-based engineering applications, Bayesian “regression” methods were used, and the uncertainties of all variables comprising both the seismic demand and the liquefaction resistance were estimated and included in the analysis. The resulting correlations were developed using a Bayesian framework and are presented in both probabilistic and deterministic formats. The results are compared to previous probabilistic and deterministic correlations.     

RTM Hemp Fibre-Reinforced Polyester Composites

Hemp fibre-reinforced polyester composites were prepared using a Resin Transfer Moulding (RTM) technique and the flexural and impact behaviour investigated. Flexural stress at break and flexural modulus showed an increasing trend with fibre content. Impact strength was found to decrease at low fibre content, then gradually increase with further addition of fibres.A strong interfacial adhesion between hemp and polyester was obtained using chemically modified hemp. This modification consisted in introducing reactive vinylic groups at the surface of the fibres, via esterification of hemp hydroxyl groups, using methacrylic anhydride. Increased bonding between fibres and matrix did not affect the flexural stress at break of the composite but was detrimental to toughness. This behaviour was ascribed to a change in the mode of failure, from fibre pull-out to fibre fracture, resulting in a marked reduction in the energy involved in the failure of the composite, leading to a more brittle material.     

Magnesite concentration technology and caustic – calcined product from Turkish magnesite middlings by calcination and magnetic separation

This paper deals with the current magnesite concentration technology and upgrading studies in Turkey, which is the second biggest magnesite and third biggest sinter magnesia producer in the world. Magnesite heat treatment and magnetic separation fundamentals are also covered. This study aims to concentrate magnesite middlings containing the silica/iron impurities from Kütahya, Turkey, by calcination and dry magnetic separation. Final calcined MgCO₃ product contains 89.57% MgO, 0.96% SiO₂, 0.43% Fe₂O₃, 2.35% CaO and 6.64% loss of ignition. The optimum particle size was determined at ?8 + 0.5 mm at 1000°C. Final product is saleable for industrial applications (i.e., soil decontamination, panels, fertilizers, animal nutrition, abrasives).     

Influences of annealing temperature on anti-reflective performance of amorphous Ta2O5 thin films

Influences of thermal annealing on structural, optical and morphological properties of the tantalum pentoxide (Ta₂O₅) thin films were investigated and anti-reflective performances were discussed in detail. The Ta₂O₅ thin films were deposited onto Corning Glass (CG), Si, GaAs and Ge substrates by radio-frequency (RF) magnetron sputtering technique using Ta₂O₅ ceramic target. The obtained secondary ion mass spectroscopy (SIMS) analysis results showed that uniform Ta and O distribution have formed throughout depth of the films deposited on substrates. The X-Ray diffraction (XRD) results indicated that the annealed Ta₂O₅ thin films at 100, 200, 300 and 500?°C have exhibited amorphous (a-Ta₂O₅) characteristic. The increased temperature has resulted in increasing the surface roughness from 0.67 to 1.60?nm. The optical transmittance of the annealed thin films has increased from 70.85 to 80.32% with increasing temperature. Spectroscopic ellipsometer (SE) measurement results demonstrated that the increased temperature has increased the refractive index of the Ta₂O₅ thin film from 2.11 to 2.18. The Ta₂O₅ thin film has reduced the average optical reflectivity of the Si, GaAs and Ge substrates by 78, 55 and 70%, respectively. In addition, thermal annealing process has decreased the optical reflectivity of the film. The obtained experimental results showed that single-layer Ta₂O₅ thin films can be used as anti-reflective layer in optical and optoelectronic applications. The best optical transmittance and anti-reflective performance were obtained at the annealing temperature of 500?°C.     

Development of Fiber-Reinforced Polymer Roof-to-Wall Connection

A significant proportion of damage to buildings in hurricanes occurs owing to weak roof-to-wall connections. The objective of this study was to develop an innovative, efficient, and nonintrusive roof-to-wall connection for wood-frame structures by using high-performance fiber reinforced polymer (FRP) composites. Several connection configurations were developed and tested at the component level under uplift loading. The most feasible configuration was selected and further tested at the component level under lateral loadings. The selected FRP tie system was then tested at a full-scale model designed to represent conventional wood-frame buildings. The objective was to assess the connection’s in situ performance under simulated uplift forces. The results of the full-scale tests were in close agreement with those obtained from the component-level tests. Control tests were also performed to evaluate the load capacity of a typical commercial metallic hurricane clip to facilitate comparison of its results with that of the newly developed FRP tie. The FRP tie system described in this study offers an easy-to-apply, nonintrusive, and viable alternative to existing metal hurricane clips for both new construction and existing structures.     

Particle-phase dry deposition and air-soil gas-exchange of polybrominated diphenyl ethers (PBDEs) in Izmir, Turkey

The particle-phase dry deposition and soil-air gas-exchange of polybrominated diphenyl ethers (PBDEs) were measured in Izmir, Turkey. Relative contributions of different deposition mechanisms (dry particle, dry gas, and wet deposition) were also determined. BDE-209 was the dominating congener in all types of samples (air, deposition, and soil). Average dry deposition fluxes of total PBDEs (sigma7PBDE) for suburban and urban sites were 67.6 and 128.8 ng m(-2) day(-1), respectively. Particulate dry deposition velocities ranged from 11.5 (BDE-28) to 3.9 cm s(-1) (BDE-209) for suburban sites and 7.8 (BDE-28) to 2.8 cm s(-1) (BDE-154) for urban sites with an overall average of 5.8 +/- 3.7 cm s(-1). The highest sigma7PBDE concentration (2.84 x 10(6) ng kg(-1) dry wt) was found around an electronic factory among the 13 soil samples collected from different sites. The concentration in a bag filter dust from a steel plant was also high (2.05 x 10(5) ng kg(-1)), indicating that these industries are significant PBDE sources. Calculated net soil-air gas exchange flux of sigma7PBDE ranged from 11.8 (urban) to 23.4 (industrial) ng m(-2) day(-1) in summer, while in winter it ranged from 3.2 (urban) to 11.6 (suburban) ng m(-2) day(-1). All congeners were deposited at all three sites in winter and summer. It was estimated that the wet deposition also contributes significantly to the total PBDE deposition to soil. Dry particle, wet, and gas deposition contribute 60, 32, and 8%, respectively, to annual PBDE flux to the suburban soil.     

1.25(OH)2 cholecalciferol pulse therapy and the effects of different dialysis membranes on serum PTH levels of haemodialysis patients

Either oral, intravenous or subcutaneous 1.25(OH)2 cholecalciferol is used in the therapy of hyperparathyroidism, which is a serious complication in patients on haemodialysis. We studied a total of 30 patients (10 women and 20 men) and divided them into two groups depending on the different types of dialysis membranes used. In the polysulfone group, mean age was 43.7 +/- 0.97 years and the average dialysis period lasted 29.9 +/- 1.23 months. For the 15 cases in which we used cuprophane membrane the mean age was 40.2 +/- 1.31 years and the average dialysis period lasted 16.2 +/- 0.86 months. The calcium level of the dialysate in both groups was 1.5 mmol/l. According to the study protocol, the determined oral calcitriol dose was 0.07 mg/kg and it was administered intermittently. After one month on high dose calcitriol therapy, treatment was continued with a maintenance dose of 0.03 mg/kg for a further six months. As a phosphate binding agent, daily 3 g calcium carbonate was administered. Before starting this treatment protocol, patients went on a 1 mg/day calcitriol therapy, although the mean PTH level was 424.63 pg/ml and the mean serum alkaline phosphatase level was 290.2 U/l. During the pretreatment period, levels of PTH, alkaline phosphatase, ionized calcium, and total calcium remained significantly within normal limits as a result of the new therapy protocol applied. PTH and phosphorus clearance rates were compared in the patient groups in which different dialysis membranes had been used. PTH and phosphorus clearances were 15.2 +/- 3 ml/min and 239.1 +/- 19.2 ml/min, respectively, in the polysulfone membrane group, and 1.1 +/- 0.3 ml/min and 112.8 +/- 9.88 ml/min, respectively, in the cuprophane membrane group (p < 0.05).