Proposed fibrinogen standard material with purified fibrinogen for plasma fibrinogen measurement on coagulation analyser

A commercially available fibrinogen standard calibrated by a World Health Organization (WHO) reference material is widely used in Japan, and most clinical laboratories use the Clauss method for plasma fibrinogen measurement. However, a current issue in fibrinogen measurement is poor laboratory-to-laboratory variability. To improve the reliability of fibrinogen values and thereby solve the poor precision and accuracy of plasma fibrinogen testing, the present paper develops a simple and large preparation procedure for a suitable fibrinogen standard and quality control material and evaluates their basic performance. With a new procedure getting high purified fibrinogen by glycine precipitation, the calibrator determined by both the Clauss and Jacobson methods produced a fibrinogen concentration of 2.20 g l(-1). The total precision of the calibrator was excellent (coefficient of variation 1.4-2.1%) in comparison with current plasma fibrinogen materials from the WHO (#98/612) and with a commercial standard (CV 1.9-3.9%). The within-run precision of the calibrator on the coagulation analysers was 1.7-2.8%. Within-analyser variability among the five instruments had good consistency (mean 2.20 +/- 0.022 g l(-1); CV 1.0%). The degradation study of the calibrator suggested that storage at 9( degrees )C for two years was as predicted. In conclusion, the results show that the calibrator prepared herein can be useful as a candidate Japanese fibrinogen standard and is applicable to automated and semi-automated coagulation analysers. Additionally, it is expected that it will be widely used in Japan by diagnostic manufacturers and clinical laboratories as a recommended secondary standard to estimate a fibrinogen value according to the WHO primary standard.     

New formation process of plating thin films on several substrates by means of self-assembled monolayer (SAM) process

This review describes our recent works on the preparation of Ni-alloy films deposited by electroless deposition as a diffusion barrier layer for ultra large-scale integration (ULSI) interconnects by using an all-wet process.In this process, we create a novel wet fabrication process including a self-assembled monolayer (SAM) as an attachment technique between diffusion barrier layer and a substrate. Our proposal process was applied to the substrates of SiO₂/Si and both organic (methyl silsesquioxane) and inorganic (hydrogen silsesquioxane) low-k dielectrics. The key technique of this proposed process is using SAM as a catalyst trapping layer. The Ni-alloy films such as NiB were deposited on catalyzed SiO₂ or low-k substrates. The electrolessly deposited NiB films were found to exhibit sufficient thermal stability and an acceptable barrier property for preventing Cu diffusion into the SiO₂ and low-k dielectrics.     

How informed are messaging app users about politics? A linkage of messaging app use and political knowledge and participation

Mobile messaging apps, such as Snapchat, Facebook Messenger, and WhatsApp, were unique campaign and information platforms in the 2016 U.S. presidential election. This study assesses how using such apps for campaign information is related to political knowledge and participation. Data from an online survey conducted prior to the election indicate that using messaging apps for news is positively related to knowledge miscalibration. Knowledge miscalibration is positively related to offline and online political participation. Findings are discussed in terms of the role of messaging apps in the political process.     

Selective oxidation of FeCr alloys in the 295–450 K temperature range

A series of iron-chromium alloys were oxidized for 10² to 6×10⁴ s in air and in the 295–500 K temperature range. Room-temperature oxidation of iron, chromium, antimony, and copper were also conducted at extended times. Oxidation characteristics such as oxide thickness and composition of the oxide and of the underlying alloy were evaluated from measurements by electron spectroscopy for chemical analysis (ESCA). An initial selective oxidation of chromium with a concomitant chromium depletion in the alloy was found. This initial oxidation step is followed by growth of an outer, iron rich oxide which causes the former chromium depletion to vanish. Apparent activation energies extracted from parabolic oxidation kinetics (295–500 K) of the investigated metals were found to be in the 10–20 kcal/mole range.     

Corrosion behavior of titanium-clad carbon steel in weakly alkaline solutions

The electrochemical polarization curves and corrosion potentials during long-term immersion of Ti, carbon steel, carbon steel tightened-Ti and Ti-clad carbon steel specimens were investigated in bentonite-contacting solution (mixture of sodium sulfate and sodium carbonate solutions), sodium sulfate solution and borate solution adjusted to pH=9.0-9.84. Ti and carbon steel were passivated during immersion in borate solution, while carbon steel was corroded in the solutions containing SO₄²⁻ ions. The immersion potentials of Ti-clad steel and steel-tightened Ti specimens were controlled by the corrosion potential of carbon steel (about 0 V vs. RHE at 298 K). The Ti side of the clad specimen was, therefore, polarized cathodically at this immersion potential, and this caused hydration of and/or hydrogen penetration into the oxide film, resulting in degradation of its barrier property. Furthermore, the cathodic current on the Ti side was partially coupled with the anodic current in the corrosion reaction on the carbon steel side, resulting in acceleration of the overall corrosion rate.     

Application of AC resistmetry to monitoring of localized corrosion of iron

The electric resistance of an iron wire electrode was traced during a potential sweep in a neutral borate buffer solution. The dissolution depth calculated from resistance change due to iron dissolution in the active potential region was in a good agreement with that calculated from the electric charge. Using a wire electrode with a diameter of 100 μm, the resolution of the dissolution depth was in the order of nm. When Cl⁻ ions were added to induce pitting, resistance increased more rapidly than that predicted from uniform dissolution. From comparison of resistance change, electric charge of iron dissolution, and surface observations using an scanning electron microscope and optical microscope, the degree of nonuniform dissolution was evaluated.     

Sensor design and image accuracy for application of capacitance CT to the petroleum refinery process

Fluid catalytic cracking (FCC) catalysts are used to produce high-quality petroleum from residual oil by the contact cracking process in the petroleum refinery. The key point in producing high-quality petroleum from residual oil is uniform fluidization at the mixing point. The sensor for capacitance computed tomography (CT) is designed to visualize the powder concentration in the process of mixing air and FCC catalysts in a vertical pipeline. The concentration distribution images are obtained under certain air-catalyst parameter conditions. The relationship between the air-catalyst parameter condition and the powder distribution is analyzed in detail. Moreover, the accuracy of the reconstructed image is discussed systemically in terms of volume fraction, residual capacitance, and capacitance correlation.     

Obstacle avoidance of snake robot by switching control constraint

In this paper, we propose an obstacle avoidance method for autonomous locomotion control of a snake robot. The snake robot consists of rigid links, active joints and passive wheels, and can move only by varying its shape. The pass planning for the obstacle avoidance is a complicated problem because the snake robot has many states, control inputs and the under-actuated property. In our proposed method, the snake motion is restricted to a periodic undulate curve (called a serpenoid curve) by an additional control constraint and the undulate curve is tuned by switching the control constraint in order that the snake robot avoids the obstacle. Therefore, the path planning is simplified and the snake robot will achieve the obstacle avoidance with an efficient path. In this paper, we denote the details of our method and investigate the effectiveness of our strategy by numerical simulations.     

Adsorption of silane coupling agent on Co-γ-Fe2O3 a nd its effect on dispersibility

The adsorption of a new type of silane coupling agent containing polyethylene oxide (EOS) on cobalt-modified iron oxide (Co--Fe₂O₃) particles and its effect on dispersibility are examined by measuring the surface chemical properties. The EOS is adsorbed on Co--Fe₂O₃ in the form of a monolayer and reduces the hydrophilicity of the surface of the particles with the adsorption. The surface hydrophilicity of EOS-treated iron foil (the iron foil has an ideal iron oxide surface) becomes lower with the increasing heat-treatment temperature. Heat treatment at 80°C or higher is required to achieve chemical bonding between EOS and the iron foil. By the same heat treatment, EOS polymerizes on the iron foil resulting in the formation of a polysiloxane network. The dispersibility of the particles in vinyl chloride-vinyl acetate-vinyl alcohol copolymer solution is improved dramatically by the surface treatment with EOS. The improvement in dispersibility is explained by considering the increase of the wettability of Co--Fe₂O₃ for the solvent due to EOS treatment.[/p]     

Microstructure and Mechanical Properties of Warm-Sprayed Titanium Coating on Carbon Fiber-Reinforced Plastic

Polymer materials are increasingly dominating various engineering fields. Recently, polymer-based composite materials’ surface performances—in particular, surface in relative motion—have been improved markedly by thermal spray coating. Despite this recent progress, the deposition of high-strength materials—producing a coating thickness of the order of more than 500 μm—remains highly challenging. In the present work, a highly dense and thick titanium coating was successfully deposited onto the carbon fiber-reinforced plastic (CFRP) substrate using a newly developed high-pressure warm spray (WS) system. The coating properties, such as hardness (300 ± 20 HV) and adhesion strength (8.1 ± 0.5 MPa), were evaluated and correlated with the microstructures of the coating. In addition, a wipe-test and in situ particle velocity and temperature measurement were performed to validate the particle deposition behavior as a function of the nitrogen flow rate in the WS system. It was found that the microstructures, deposition efficiency, and mechanical properties of the coatings were highly sensitive to nitrogen flow rates. The coating porosity increased with increasing nitrogen flow rates; however, the highest density was observed for nitrogen flow rate of 1000 standard liters per minute (SLM) samples due to the high fraction of semi-molten particles in the spray stream.