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[en] 3-Hydroxykynurenine (3-HK), which is an endogenous metabolite of tryptophan in the kynurenine pathway, is a potential neurotoxin in several neurodegenerative disorders. Epigallocatechin 3-gallate (EGCG), a major compound of green tea, is recognized as a promising natural substance for protection against neuronal diseases. This study investigated the possible protective roles and mechanism of EGCG, against 3-HK-induced cell death. It was found that 3-HK induces neuronal cell death in the human neuroblastoma SH-SY5Y cell line. The reduced cell viability produced characteristic features such as cell shrinkages, plasma membrane blebbing, chromatin condensation, and nuclear fragmentation. The cells treated with 3-HK showed an increase in the concentration of reactive oxygen species (ROS) as well as in caspase activity. In addition, both are involved in the 3-HK-induced apoptosis. EGCG attenuated the cell viability reduction by 3-HK in both a dose- and time-dependent manner. Optical microscopy showed that EGCG inhibited the cell morphological features in the 3-HK-treated cells. Furthermore, the increase in the ROS concentration and the caspase activities by 3-HK were also attenuated by EGCG. These results showed that EGCG has a protective effect on the 3-HK induced cell death by inhibiting ROS production and caspase activity. The results suggest that EGCG might be a promising protective substance against the neuronal degenerative diseases
[en] We discuss the open string one-loop partition function in the tachyon condensation background of an unstable D-brane system. We evaluate the partition function by using the boundary-state formulation and find that it is in complete agreement with the result obtained in the boundary string field theory. This suggests that the open string higher loop diagrams may be produced consistently by using a closed string field theory, where the D-brane plays the role of a source for the closed string field
[en] This study focused on the synthesis of NbxSrTi1-xO3 photocatalysts which partially inserted Nb ions with excellent ability of fluorescence into the perovskite structured SrTiO3 frameworks and their photocatalytic hydrogen productions from methanol/water splitting corresponding to the molar ratios of Ti and Nb. The characteristics of the synthesized SrTiO3 and NbxSrTi1-xO3 powders were analyzed by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS), and UV-Visible spectrometer. The hydrogen evolution from methanol/water photo-splitting was enhanced over Nb0.05SrTi0.95O3 compared to those over SrTiO3 and another NbxSrTi1-xO3; 4.9 mL of hydrogen gases was collected after 8 h when 0.5g of Nb0.05SrTi0.95O3 catalyst was used in pH 10
[en] To evaluate the findings of first-pass perfusion CT in hyperacute stroke patients and to determine the relationship between a perfusion map and final infarct outcome. Thirty-five patients admitted with ischemic stroke within six hours of the onset of symptoms underwent conventional cerebral CT immediately followed by first-pass perfusion CT. Nineteen underwent follow-up CT or MRI, and three types of dynamic perfusion map-cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) - were evaluated by two radiologists. In these 19 patients, initial perfusion maps correlated with final infarct size, determined during follow-up studies. In all 35 patients, major large vessel perfusion abnormalities [middle cerebral artery - MCA MCA and anterior cerebral artery - ACA (n=2); posterior cerebral artery - PCA (n=8)] were detected. On first-pass perfusion maps depicting CBF and MTT, all lesions were detected, and CBF and delayed MTT values were recorded. CBV maps showed variable findings. In all 19 patients who were followed up, the final infarct size of perfusion abnormalities was less than that depicted on CBF and MTT maps, and similar to or much greater than that seen on CBV maps. First-pass perfusion CT scanning is a practical, rapid and advanced imaging technique. In hyperacute stroke patients, it provides important and reliable hemodynamic information as to which brain tissue is salvageable by thrombolytic therapy, and predicts outcome of such treatment
[en] To minimize the cost and loss rate of energy artificial room ventilation system, the O_2 separator was suggested for the flow of the excessive ventilation amount between indoor and outdoor because the pure O_2 separated and concentrated by the O_2 separator can be supplied with the ventilation amount minimized. How the O_2 separator applies to ventilation and its operation characteristics were investigated by controlling under various conditions as well as the operation conditions optimized required for indoor air quality such as the concentration of CO_2 and O_2. Consequently, it was known that the O_2 concentration was increased; however, the increase of the CO_2 concentration was suppressed by the sufficient supply of O_2 concentrated from the storage tank into the room despite the two persons’ breathing in the room having an inner volume of about 56m"3. Consequently, it was concluded that the supply system of the concentrated O_2 which was stored into the tank after the production with the O_2 separator can be applied to the room ventilation system for the improvement of the indoor air quality.
[en] High purity O_2 concentrated by the PSA-type O_2 separator was applied to a room ventilation system combined with CO_2 adsorption module to remove the indoor CO_2 for the indoor air quality. And then the room was occupied by several persons to breathe for the O_2 consumption and CO_2 generation. As a result, the indoor air quality was improved by the ventilation system combined with the O_2 supply and the CO_2 adsorption module. It was due to the fact that the CO_2 concentration was not steeply increased, but also even decreased and then the increasing rate of the O_2 concentration with the O_2 supply was simultaneously increased by the CO_2 removal despite the CO_2 generation and O_2 consumption with the four persons' breathing. As a representative result, in the case of supplying the high purity O_2 of 30 L/min under using the CO_2 adsorption module, the best performance with the highest increasing rate of O_2 concentration and the lowest increasing rate of CO_2 concentration was obtained among the various cases, and then the increasing rates of CO_2 radiation and O_2 concentration were -2.3 ppm/min and 33.3%/min, respectively.
[en] Solitary extramedullary plasmacytoma (SEP) of the thyroid is uncommon and mostly occur in patients with a Hashimoto's thyroiditis (82%). We present a case on SEP of thyroid in Hashimoto's thyroiditis, which mimics growing benign cystic masses on serial ultrasonography.
[en] Fibrolipomatous hamartoma (FLH) of the nerve is a rare, benign tumor that most commonly originates from the median nerve of the hand. Fibrofatty tissue proliferates around the nerve and infiltrates the epineurium and perineurium. We present two cases of pathologically proven FLH of a digital branch of the median nerve, without macrodystrophy with magnetic resonance imaging, surgical and pathologic findings. Magnetic resonance images of both cases show well-circumscribed mass with fat signal intensity around an enlarged digital branch of the median nerve and characteristic coaxial-cable-like appearance on axial images and spaghetti-like appearance on coronal images.
[en] In this review work, energy harvesting methods for waste heat with small temperature differences between heat source and sink are discussed. At present, many methods are tried and employed to utilize this type of waste heat. A typical example is found in a conventional power generation system. By utilizing this type of waste heat, additional energy can be produced in regular power generation systems. Up to this point, two energy harvesting methods have been introduced and applied for the use with this type of waste heat. One is a method using an organic Rankine cycle (ORC) while the other is a method using a thermoelectric generation (TEG). An ORC is a Rankine cycle that can be applied to this type of waste heat using organic fluids such as refrigerants as working fluids instead of water used in a typical Ranking cycle. On the other hand, a TEG utilizes Peltier, Seebeck, and Thomson effects caused by the temperature difference between the heat source and sink for energy harvesting. In this work, various aspects associated with the use ORC and TEG for waste heat harvesting with small temperature differences between the heat source and sink.
[en] Recently, studies of partially insulated, high-temperature superconducting (HTS) coils have shown application in the design and construction of compact, stable and self-protecting HTS coils. This article presents the electrical characteristics of HTS coils based on the turn-to-turn inserted materials and conditions. Three partially co-wound pancake coils were fabricated and tested. Each coil was partially co-wound with Kapton, stainless steel and copper tape at every fourth turn of the winding. Tested coils were co-wound on every turn with Kapton, stainless steel and copper tape, and coils without turn-to-turn insulation were the control group. Charge–discharge, sudden-discharge and over-current tests were performed to evaluate the performance of the fabricated coils. The experimental results show that the properties of materials inserted into the coil can control the time constant (τ). Therefore, HTS coils can be designed for specific purposes according to the time constant control. The experimental results of the study could be useful in designing HTS coil applications. (papers)