Proteins synthesized in living cells often fail to properly fold, and misfolded proteins are potentially toxic to cells due to the existence of exposed hydrophobic surfaces. For example, misfolded proteins tend to aggregate each other and capture other normal proteins into aggregates. Genetic mutations often cause protein misfolding, and these mutations induce neuronal cell death in neurodegenerative diseases (e.g. Alzheimer's disease, Parkinson's disease, polyglutamine disease and amyotrophic lateral sclerosis). However, how misfolded proteins exert cytotoxicity is poorly understood. In living cells, there are two strategies to prevent the toxicity of misfolded proteins: one is prevention of aggregation by molecular chaperones and the other is degradation by proteases. These two systems coordinately monitor quality of proteins and decide the fate of proteins (e.g., reuse after refolding or destruction by protease digestion). We have used aggregation-prone proteins tagged with green fluorescent proteins and derivatives to analyze the dynamics of cytotoxic misfolded proteins in living cells. We discuss how fluorescently labeled proteins are useful to understand the dynamics of misfolded proteins, particularly for those causing neurodegenerative diseases. We also discuss kinetics of interaction between misfolded proteins and binding proteins like molecular chaperones.

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Currently, the monitoring, surveillance and management problem of transport means are very important and can be solved successfully in many developed countries. But in Vietnam due to different, complex conditions of transport infrastructure, weather conditions, financial potentiality, legislation, many similar systems imported from overseas companies are not applicable. This paper proposes some successful solutions for this problem in Vietnam based on application of new technologies such as GPS, DSP and image processing. These solutions include the monitoring and management system for transport means in open-cast mining, monitoring and warning systems in long-distance buses, and surveillance systems by camera on the road.

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This study presents results from a study of fine grinding in limestone conducted using a super centrifugal mill (SC-mill), a type of circular stirred mill. The effects of the operational conditions in the SC-mill such as rotor speed, grinding time, the mass of the grinding media, and the mass of the feed sample on the fine grindability of limestone were investigated for 0.5 and 0.8mm grinding media. The results suggest that the mass and the specific surface area of the fine particles produced by the SC-mill could be expressed as functions of the operational conditions mentioned above for the respective grinding media size.

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Methanol oxidation is the anodic reaction in a direct methanol fuel cell (DMFC). The development of a new catalyst, which can efficiently promote the anode reaction, is very important. In this study, a Pt thin film and two kinds of Pt oxide thin films prepared by reactive sputtering were characterized by XRD, XPS and EPMA, then their methanol oxidation activities were investigated using the rotating disk electrode method in a (H₂SO₄+CH₃OH) solution. The Pt, PtO and PtO₂ thin films were obtained by sputtering a Pt target in 100% Ar, Ar - 50% O₂ and 100% O₂ plasma, respectively. Neither PtO nor PtO₂ had an excellent activity when the thin films were used as-received. However, an apparent catalytic activity of methanol oxidation was observed in the partially reduced Pt oxide thin films, whose ratios of O/Pt were significantly decreased by passing a cathodic current. On the other hand, the methanol oxidation activity of the Pt thin film was hardly changed by the electrochemical reduction. The methanol oxidation current showed that the electrocatalytic activity of the partially reduced Pt oxide thin films was about hundred times higher than that of the Pt thin film. Therefore, the partially reduced Pt oxide is a material with a significant potential for use as a catalyst for not only the DMFC, but also a fuel cell using the carbon compound as the fuel.

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Conventional smelting with a carbon reductant is not used to obtain metals with high affinity for oxygen. Molten salt electrolysis is often used for the extraction of such metals. Although no carbon dioxide emission is expected in principle, huge amounts of CO₂ are generated in actual molten salt electrolysis, where graphite electrodes are used as anodes. This is why the graphite is an indispensable material for high-temperature molten salt. For example, more than 1.2 tons of CO₂ are emitted per 1.0 ton production of aluminum in a conventional molten salt electrolysis. We are developing a CO₂-free process using arc electrodes. Alumina (Al₂O₃) mixed cryolite and AlF₃ are used as test materials. Electrolysis is conducted in a stainless steel chamber under an inert Ar atmosphere. The arc is generated as a gaseous anode using a water-cooled plasma torch in constant current mode. The production of aluminum was confirmed by the experiment.

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An activated carbon with a high microporosity and mesoporosity, as well as a high bulk density, was fabricated by activating the extrusion-molded precursor made from carbonized rice husk (RH) and beet sugar (BS) at 850°C in CO₂. The pore structure of the activated carbon based on the mixture of RH and BS (RHBSAC) was analyzed in relation to the bulk density. The extrusion molding was very useful to increase the bulk density. RHBSAC which was first activated for 1 h was immersed again in the BS syrup and then activated in CO₂ for 2 h. This two-step activation process provided both a high bulk density (0.93 g/cm³) and a microporous and mesoporous structure (BET specific surface area: 844 m²/g, total pore volume: 0.53 cm³/g, micropore volume: 0.29 cm³/g, and mesopore volume: 0.19 cm³/g).

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In order to remove molybdenum (Mo) from the high-level radioactive liquid waste (HLLW), Pb-Fe based adsorbents were synthesized and their adsorption capacities were investigated. The adsorbent precursors were prepared with precipitation at various pH values by adding sodium hydroxide into a mixture of 1 mol/L lead nitrate and 1 mol/L ferric nitrate aqueous solutions, and each precipitate was then filtered, dried and ground to obtain a fine powder precursor. The precursors were also calcinated at various temperatures to obtain the Pb-Fe based adsorbents.
Two main parameters were considered when synthesizing the adsorbents, i.e. the pH value of precipitation of adsorbent precursor as well as the calcination temperature of the Pb-Fe based adsorbent. The experimental results indicated that the calcination temperature has a great influence on adsorption capacity of the Pb-Fe based adsorbent for Mo. It was found that when the precursor was precipitated at pH 9 and then calcinated at 500 °C, the sorbed amount of Mo by the adsorbent was the highest. In addition, the equilibrium sorption isotherm of Mo onto the adsorbent was estimated by the Langmuir, Freundlich and Redlich-Peterson sorption models. We found that the overall adsorption process was described well by Redlich-Peterson sorption isotherm equation.

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Polylactic acid (PLA) is a biodegradable, eco-friendly plastic that is attracting more attention than any other plastic of its kind. In this study, the authors examined the effects of ultraviolet light on the mechanical and electrical characteristics of PLA in order to clarify the prospects of using PLA as an electrical insulator material. An examination of the tensile stress curves versus the elongation showed that the stress and elongation of PLA decreased with an increase in the time length of the UV irradiation and that this decrease in the elongation was significant. The authors found that the dielectric breakdown strength (E_B) is temperature dependent; that is, with an increase in the time length of the UV irradiation, the E_B of PLA had a tendency to decrease over a wide temperature range.

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TiO₂ pillared mica was prepared using Ti ion species as TiO₂ precursor. The titanium ion species were obtained by an addition of several titanium alkoxides to an aqueous solution of CH₃COOH, with different CH₃COOH/Ti ratios and temperatures. The structure and properties of the TiO₂ pillared mica was studied by X-ray diffraction, N₂ adsorption, FT-IR and TG-DTA. After calcined at 500°C, the BET surface area of samples varied between 250 and 460 m²/g. The sample prepared using titanium tetraethoxide as titanium source possessed well ordered structure and higher BET surface area. The basal spacing of TiO₂ pillared mica was increased with the decrease in CH₃COOH/Ti ratio and the increase in temperature of preparation of titanium ion species, while the degree of ordered structure of pillared mica was decreased.

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Conversion of three different types of incineration ash, coal fly ash (CFA), paper sludge fly ash (PSFA) and industrial waste incineration fly ash (IWIFA) into useful materials using the alkali fusion method is attempted. The chemical and mineralogical compositions of these ashes differed. The order of Ca content in the ash was IWIFA>PSFA>CFA, while the Si and Al contents in the ashes were CFA>PSFA>IWIFA. CFA was mainly composed of quartz [SiO₂] and mullite [3Al₂O₃·2SiO₂], PSFA mainly of gehlenite [Ca₂Al₂SiO₇], anorthite [CaAl₂Si₂O₈] and talc [Mg₃Si₄O₁₀(OH)₂], and IWIFA mainly of portlandite [Ca(OH)₂], halite [NaCl] and sylvine [KCl]. Zeolites (zeolite-X, -A, -P and hydroxysodalite), hydrogrossular (katoite), and calcite were synthesized from the ashes. With an increasing Ca content of the ash, the Si concentration in the solution decreased, and the main product phases changed from zeolite (aluminosilicate) to hydrogrossular (calcium aluminosilicate), and finally to calcite (calcium carbonate). The observed concentrations of Si, Al, and Na in the solution during the reaction explain the crystallization of these phases.

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In an attempt to raise the copper grade of Printed Circuit board (PCB) by removing other components, carbonization treatment was investigated. The crushed PCB without surface-mounted parts was carbonized under nitrogen atmosphere. After screening, the char was classified by size into oversized pieces, undersized pieces and powder. The copper foil and glass fiber pieces were liberated and collected in undersized fraction. The liberation of copper foil from the oversized pieces was also investigated. The copper foil was liberated easily from glass fiber by stamping treatment. Liberation rate of copper foil was high at high carbonized temperature. The experimental results indicated that 90% of oversized char was liberated and the copper foil recovery from PCB carbonized at 1073 K was 110 kg/t. The copper recovery from char powder by flotation was also investigated. 15% of the copper grade and 80% of the copper recovery were obtained.

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The effect of temperature and environment (air, humidity and 3.5 wt% NaCl salt spray) on cyclic fatigue life and fracture mechanism on 2524 aluminum alloy was investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fatiguae property testing. The results showed that temperature has a detrimental influence on cyclic fatigue life. The cyclic fatigue strength n=10⁶ at elevated temperature (100%°C) decreased by 30 MPa compared to that at cryogenic temperature (-55°C). Moreover, temperature also remarkably affected the feature of dislocation, second-phase particles and grain boundary. The fracture surface at cryogenic temperature showed crystallographic morphology. The dominant deformation process at ambient and elevated temperature was a combination of predominantly transgranular and local intercrystalline fracture mechanism. The fractographic features revealed the fatigue crack growth behavior of the alloy in three environments, more brittle striations were observed in humidity air and salt spray. The increased crack growth rate was attributed to a combination of hydrogen embrittlement and anodic dissolution at the tip of crack.

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We have already developed a new recycling system for high water content mud such as construction sludge by using paper debris (fragments of the newspaper) to increase the recycling rate of the construction sludge. However, recently, the price of old newspaper is increasing. Therefore, development of inexpensive fiber materials are strongly desired in order to reduce the recycling cost. In this study, the applicability of waste gypsum board paper instead of paper debris was experimentally investigated. The waste gypsum board paper was crushed by the hammer mill and crushed paper was used in fiber-cement-stabilized-soil method. It was found through the unconfined compression tests that the failure strength and failure strain of modified soils by using crushed board paper are almost the same as those of modified soils by using paper debris. That is, it was confirmed that the crushed board paper can become a substitute of paper debris.

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When an inversion layer forms, particulate matter (PM) stagnates in the upper part of the inversion layer. The PM falls to the ground as an inversion layer collapses. This phenomenon generally called fumigation. We sampled radiation fog by constant volume (50 mL) continuously from occurrence to disappearance of radiation fog at Takanosu Basin to clarify the pollution mechanism of radiation fog by fumigation. Our results show that the absolute equivalent of pollutants in fog water such as (NH₄)₂SO₄ and NaCl for eight events increased during the early morning, immediately before the disappearance of radiation fog. Using the series sampling by constant volume of the radiation fog, it was clarified that the increase in pollutant of air by fumigation results in the increase of pollutant in fog droplets.

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A novel detection system for second harmonic ultrasonic pulse waves is constructed by modifying the double-layered piezoelectric transducer (DLPT). The new DLPT composed of two PbTiO₃ thickness-mode piezoceramic concave disks is employed: one is a conventional concave transducer and the other is a ring type concave transducer. Since the switch for the electrical connection used in the conventional DLPT system is not required, a simple system for detecting second harmonic ultrasonic pulse waves can be constructed. Furthermore, for real time detection of second harmonic ultrasonic pulse waves, pulse inversion averaging (PIA) is carried out. As a result, the enhanced second harmonic ultrasonic pulse waves are displayed on an oscilloscope in real time. A drilled hole in an aluminum plate is then imaged to demonstrate the effectiveness of this system.

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The permeability of rock matrices is not routinely measured because the equipment is expensive and the measurements are time-consuming. We designed a new laboratory permeability test using low-cost apparatus and investigated its performance. The method is a variation of the falling head method, in which the standpipe used as the pressure source is replaced with a pressure accumulator. High pressure is applied to a rock specimen, making it possible to measure permeability within an hour. The apparatus produces radial flow from the surface to a central hole drilled in a cylindrical specimen. We determined that the apparatus measures hydraulic conductivity in the range of 3.5×10^-10 to 2.6×10^-4 cm/s. The error in hydraulic conductivity obtained from repeated measurements is ±∼10%, and the difference in conductivity between this method and the standpipe method is ∼25%. For a rock with a hydraulic conductivity of 3.0×10^-9 cm/s, measurement takes at least 800 s.

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