• Analytical Science and Technology
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• v.14 no.4
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• pp.364-370
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• 2001

The corrosion behaviors of reinforcing steels were investigated under chloride ion contained in cement mortar including gypsum by the implementation of half cell potential measurement, EPMA analysis, exterior features, weight loss and extraction experiment. The acceleration test equipment accelerated corrosion of mild steel bar in a short period of time. From observing the exterior features and weight loss, we could evaluate the measure of corrosion. Also, from the extraction experiment of ${SO_4}^{2-}$ with $Cl^-$ ions contained in the ceramic mortar, we concluded that ${SO_4}^{2-}$ ion affected more on the corrosion mechanism in comparison to pH.

• Advances in concrete construction
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• v.2 no.2
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• pp.109-123
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• 2014

This paper presents chloride induced corrosion durability of reinforcing steel in geopolymer concretes containing different contents of sodium silicate ($Na_2SiO_3$) and molarities of NaOH solutions. Seven series of mixes are considered in this study. The first series is ordinary Portland cement (OPC) concrete and is considered as the control mix. The rest six series are geopolymer concretes containing 14 and 16 molar NaOH and $Na_2SiO_3$ to NaOH ratios of 2.5, 3.0 and 3.5. In each series three lollypop specimens of 100 mm in diameter and 200 mm in length, each having one 12 mm diameter steel bar are considered for chloride induced corrosion study. The specimens are subjected to cyclic wetting and drying regime for two months. In wet cycle the specimens are immersed in water containing 3.5% (by wt.) NaCl salt for 4 days, while in dry cycle the specimens are placed in open air for three days. The corrosion activity is monitored by measuring the copper/copper sulphate ($Cu/CuSO_4$) half-cell potential according to ASTM C-876. The chloride penetration depth and sorptivity of all seven concretes are also measured. Results show that the geopolymer concretes exhibited better corrosion resistance than OPC concrete. The higher the amount of $Na_2SiO_3$ and higher the concentration of NaOH solutions the better the corrosion resistance of geopolymer concrete is. Similar behaviour is also observed in sorptivity and chloride penetration depth measurements. Generally, the geopolymer concretes exhibited lower sorptivity and chloride penetration depth than that of OPC concrete. Correlation between the sorptivity and the chloride penetration of geopolymer concretes is established. Correlations are also established between 28 days compressive strength and sorptivity and between 28 days compressive strength and chloride penetration of geopolymer concretes.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2477-2479
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• 2012

Objective: To study the histomorphological pattern of urothelial tumors of the urinary bladder in Manipur and to evaluate whether any correlation exists between tumor grade and muscle invasion. Methods: A 10 year retrospective study of all consecutive cases diagnosed in the Department of Pathology RIMS - Imphal, between $1^{st}$ January 2001 to $31^{st}$ December 2010. Results: The study included 26 cases of transitional cell tumors of urinary bladder. The male to female ratio was 1.5:1 and the ages ranged from 38 years to 73 years (medians of 60 and 64 years, respectively). Of the total, 14 (53.9%) cases were low grade, 9 (34.6%) were high grade, 2 (7.7%) were papillomas and 1 (3.9%) was a papillary urothelial neoplasm of low malignant potential (PUNLMP). Pathological staging showed that 14 (53.9%) of the cases were stage PTa, four (15.4%) PT1, and eight (30.9%) PT2. Some 18.2% of low grade tumors and 75% of high grade tumors were invasive to the detrusor muscle layer. Conclusion: Bladder cancer is an uncommon disease, transitional tumors being the only histological type observed. It was more common in males than females, with peak incidence in seventh decade. Most of the tumors were non-invasive (PTa) and invasion to the detrusor muscle layer was seen in more than half of the high grade tumors. There is a definite correlation between advancing tumor grade and muscle invasion.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.75-82
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• 2017

The effects of acepromazine on human ether-$\grave{a}$-go-go-related gene (hERG) potassium channels were investigated using whole-cell voltage-clamp technique in human embryonic kidney (HEK293) cells transfected with hERG. The hERG currents were recorded with or without acepromazine, and the steady-state and peak tail currents were analyzed for the evaluating the drug effects. Acepromazine inhibited the hERG currents in a concentration-dependent manner with an $IC_{50}$ value of $1.5{\mu}M$ and Hill coefficient of 1.1. Acepromazine blocked hERG currents in a voltage-dependent manner between -40 and +10 mV. Before and after application of acepromazine, the half activation potentials of hERG currents changed to hyperpolarizing direction. Acepromazine blocked both the steady-state hERG currents by depolarizing pulse and the peak tail currents by repolarizing pulse; however, the extent of blocking by acepromazine in the repolarizing pulse was more profound than that in the depolarizing pulse, indicating that acepromazine has a high affinity for the open state of the channels, with a relatively lower affinity for the closed state of hERG channels. A fast application of acepromazine during the tail currents inhibited the open state of hERG channels in a concentration-dependent. The steady-state inactivation of hERG currents shifted to the hyperpolarized direction by acepromazine. These results suggest that acepromazine inhibits the hERG channels probably by an open- and inactivated-channel blocking mechanism. Regarding to the fact that the hERG channels are the potential target of drug-induced long QT syndrome, our results suggest that acepromazine can possibly induce a cardiac arrhythmia through the inhibition of hERG channels.

• Food Science and Preservation
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• v.22 no.4
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• pp.607-612
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• 2015

The aim of this research was to investigate the whitening effects of rutin and rutin metabolites including 3,4-dihydroxyphenyl acetic acid (DHPAA), 3-hydroxyphenyl acetic acid (HPAA), 3,4-dihydroxytolene (DHT) and homovanillic acid (HVA). The potent whitening effect of rutin and rutin metabolites were determined by mushroom tyrosinase inhibition assay and expressed as the half maximal inhibitory concentration ($IC_{50}$) against tyrosinase activity in vitro. The HVA showed the highest inhibitory effect ($IC_{50}=37.10{\mu}M$) of tyrosinase activity, followed by DHPAA ($IC_{50}=45.87{\mu}M$), HPAA ($IC_{50}=50.96{\mu}M$), rutin ($IC_{50}=57.98{\mu}M$), and DHT ($IC_{50}=66.09{\mu}M$), respectively. To evaluate cell cytotoxicity, MTT assay was performed with JB6 P+ mouse epidermal cells and expressed as a relative percentage of untreated control. The results showed that rutin and rutin metabolites had no cytotoxic effects on JB6 P+ cells up to $100{\mu}M$ except for DHT (up to $50{\mu}M$). These results suggests that rutin metabolites may be utilized as a potential tyrosinase inhibitors and the whitening agents for the future.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1333-1340
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• 2012

Epithelial ovarian cancer represents the most lethal gynecological cancer, and the high mortality rate makes this malignancy a major health concern. Poor prognosis results from an inability to detect ovarian cancers at an early, curable stage, as well as from the lack of an effective therapy. Thus, effective and novel strategies for prevention and treatment with non-toxic agents merit serious consideration. Resveratrol, obtained from grapes, berries, peanuts and red wine, has been shown to have a potent growth-inhibitory effect against various human cancer cells as well as in in vivo preclinical cancer models. The objective here was to evaluate potential antitumor effects of resveratrol in both in vitro and in vivo NuTu-19 ovarian cancer models. In vitro an invasion assay was performed. After 48 h, the numbers of viable cells that invaded the extracellular matrix layer were reduced by 94% with resveratrol in comparison to control. For the in vivo anti-tumor assessment, 10 rats were injected with NuTu-19 cells into the ovarian bursa. Thereafter, half were provided with a diet mixed with a dose of 100 mg resveratrol/kg body weight/day for 28 days. Following sacrifice, anticancer effects were assessed by histological evaluation of ovarian as well as surrounding tissues, and immunohistochemical detection of cell proliferation and apoptosis, but there were no observable differences between the control and resveratrol-treated groups for any of the biological endpoints. While resveratrol is effective in suppressing the in vitro cellular invasion of NuTu-19 ovarian cancer cells, these effects do not appear to impact on in vivo NuTu-19 ovarian cancers in rats.

• ALGAE
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• v.18 no.4
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• pp.281-288
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• 2003

To study the environmental features causing a bloom of the novel dinoflagellate Heterocapsa circularisquama (Dinophyceae), hydrographic and chemical aspects were measured in the Uranouchi Bay, Kochi Prefecture, Japan, from January to December, 1997. The cell density of H. circularisquama increased rapidly in early October, and dropped sharply in mid-October. Growth rate of H, circularisquama during bloom period appeared 1.50 division day$^{-1}$ under high water temperature (25$^{\circ}C$) and salinity (32 psu) conditions. Althought the result from hydrographic aspect indicated good condition for their growth, dissolved inorganic phosphorus (DIP) concentration in surface layer before bloom formation was less than 0.70uM, which is lower than their half saturation constant(Ks). Dissolved inorganic nitrogen(DIN): DIP ratio was > 30, indicating potential P-limitation. However, before bloom formation period of H. circularisquama, DIP concentrations were high in bottom layer (> 4.0 uM). Some studies reported that H. circularisquama had the ability to migrate vertically and to utilize dissolved organic phosphorus (DOP). Thus, DIP in bottom layer might have been utilized by H. circularisquama for their growth.DOP might have weakly affected their growth because of low reactive DOP concentrations owing to low DOP concentration (ca. 0.39 uM). Thus, if nutrient condition of bottom layer in Uranuchi Bay is not improved, the outbreaks of H. circularisquama red tides may became an annual feature.

• KSBB Journal
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• v.18 no.3
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• pp.207-210
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• 2003

The locus coeruleus (LC) contains about half of the total number of noradrenergic neurons in the brain and those noradrenergic neurons from the LC innervate entire brain regions. The LC is a major common target region in several neurodegenerative disorders such as Alzheimer's, Pakinson's and Huntington's diseases. The brain-derived neurotrophic factor (BDNF) regulate neuronal cell survival and differentiation of central nervous system neurons, including LC noradrenergic neurons. In this study, various small molecules and growth factors were tested as candidates to promote the production of BDNF in LC noradrenergic neuronal cells. The molecules tested include neuropeptides, cytokines, growth factors, neurotransmitters, and intracellular signaling agents. Four small molecules or growth factors, FGF8b, BMP-4, forskolin, and dibutyryl cGMP, were found to increase the release of BDNF in LC noradrenergic neurons. Especially, BMP-4 significantly enhanced BDNF production over 2.5-fold in LC noradrenergic neurons.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.203-208
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• 2016

In this study, to clarify the differences rebar corrosion beginning, through the actual corrosion accelerated test in corrosion time and laboratory test chamber of the structure of the marine environment results in both environments, it is an object of correlation coefficient derived. The accelerated corrosion test was carried out by two case, I.e., one is $20^{\circ}C$ of low temperaure codition(case 1), and the other is $65^{\circ}C$ of high temperaute codition(case 2). Whether corroions occurs, it was measures using half-cell potential method. The results indicated that case 2 is to acclerate the corrosion of rebar about 1.7~1.8 times as compared with case 1, thenthe corrosion of rebar embadded in concrete occurred according to the order of OPC60, FA, BS, OPC35. Correlation coefficient between acclerated corrosion test and long-term exposure test, case 1 is 2.45 to 2.94, and case 2 is 4.37~4.99.

• Transactions of the Korean hydrogen and new energy society
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• v.11 no.4
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• pp.189-202
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• 2000

$AB_2$ type Zr-based Laves phases alloys have been studied for potential application as a negative electrode in a Ni-MH battery. The $AB_2$-type electrodes have a much higher energy density than $AB_5$-type electrodes per weight, however they have some disadvantages such as poor activation behavior and cycle life etc. Nonetheless, the $AB_2$-type electrodes have been studied very extensively due to their high energy density. In this study, in order to develop the cycle life, the Mn of $AB_2$ alloy composition was substituted partially by Mo. The alloys were melted by arc furnace and remelted 4-5 times for homogeneity. The alloy powder was used below 200-325 mesh for experiments. The structures and phases of the alloys were analyzed by XRD, SEM and EDS, and measured the curve of a pressure-composition isotherms. The electrodes were prepared by cold pressing of the copper-coated(25 wt%) alloy powders, and tested by a half cell. The results are summarized as follows. The cycle life was improved with the increase of Mo amount in $Zr_{1-x}Ti_xV_{0.4}Ni_{1.2}Mn_{0.4}Mo_y$(x=0.3, 0.4) and the activation was faster, whereas the discharge capacity decreased.