• The Korean Journal of Physiology and Pharmacology
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• v.26 no.6
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• pp.469-478
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• 2022

WNT signaling plays an important role in cardiac development, but abnormal activity is often associated with cardiac hypertrophy, myocardial infarction, remodeling, and heart failure. The effect of WNT signaling on regulation of atrial natriuretic peptide (ANP) secretion is unclear. Therefore, the purpose of this study was to investigate the effect of Wnt agonist 1 (Wnta1) on ANP secretion and mechanical dynamics in beating rat atria. Wnta1 treatment significantly increased atrial ANP secretion and pulse pressure; these effects were blocked by U73122, an antagonist of phospholipase C. U73122 also abolished the effects of Wnta1-mediated upregulation of protein kinase C (PKC) β and γ expression, and the PKC antagonist Go 6983 eliminated Wnta1-induced secretion of ANP. In addition, Wnta1 upregulated levels of phospho-transforming growth factor-β activated kinase 1 (p-TAK1), TAK1 banding 1 (TAB1) and phospho-activating transcription factor 2 (p-ATF2); these effects were blocked by both U73122 and Go 6983. Wnta1-induced ATF2 was abrogated by inhibition of TAK1. Furthermore, Wnta1 upregulated the expression of T cell factor (TCF) 3, TCF4, and lymphoid enhancer factor 1 (LEF1), and these effects were blocked by U73122 and Go 6983. Tak1 inhibition abolished the Wnta1-induced expression of TCF3, TCF4, and LEF1 and Wnta1-mediated ANP secretion and changes in mechanical dynamics. These results suggest that Wnta1 increased the secretion of ANP and mechanical dynamics in beating rat atria by activation of PKC-TAK1-ATF2-TCF3/LEF1 and TCF4/LEF1 signaling mainly via the WNT/Ca²⁺ pathway. It is also suggested that WNT-ANP signaling is implicated in cardiac physiology and pathophysiology.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.996-1003
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• 2006

The absorption characteristics of powdered activated carbon doped by transition-metal nanoparticles were investigated to enhance the remove efficiencies of $TCOD_{Mn}$ and Color from the flexo-inks wastewater. According to the adsorption dynamics of PAC and MPAC, the optimal dosage of activated-carbon adsorbents was 3 g/L under the reaction conditions of pH6.0, 30 mill of reaction time, 240 rpm of mixing intensity. The removal efficiencies by the optimal dosages were maximized as 19% $TCOD_{Mn}$, 57% Color for PAC and 88% $TCOD_{Mn}$, 95% Color for MPAC. Freundlich indexes of isotherm absorption were estimated as follows: i) For PAC, k=-8.11, 1/n=2.98, r=0.91 in the raw water, and k=0.14, b/n=0.75, r=0.96 in the biological treatment water, ii) For MPAC, k=2.69, 1/n=0.21, r=0.80 in the raw water, and k=0.74, 1/n=1.17, r=0.95 in the biological treatment water. MPAC (Powdered activated carbon doped by transition-metal nanoaprticles) was very effective in the removal of organics from the raw water and biological treatment water, as Freundlich indexes of 1/n for both types of water were estimated less than 2.0.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1518-1522
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• 2006

In the present study, it was observed how the phage-host system that is naturally reproduced in activated sludge is affected by the host inoculation. The system of Microlunatus phosphovorus and its phages was selected as the phage-host system native to an activated sludge system operated for 19 days under sequencing anaerobic-aerobic conditions with glutamate as the main carbon source. The phage-host system related to M. phosphovorus was monitored by plaque assay for the phages and by fluorescent in situ hybridization (FISH) for the bacterial host. In addition, the whole phage structure was also monitored by pulsed-field gel electrophoresis (PFGE). During the first 9 days, the phage-host system was more or less steady at approx. 9% (FISH/ DAPI) for M. phosphovorus and approx. 10,000 PFU/ml for its lytic phages. Microlunatus phosphovorus JCM9379 was inoculated into the activated sludge on day 10. Right after the inoculation, M. phosphovorus was approx. 24% (FISH/DAPI) whereas its lytic phages dropped down to approx. 500 PFU/ ml. After the host inoculation (within 9 days), however, the phage-host system eventually reverted to its original level in each population. On the other hand, the whole phage structure was not significantly changed by M. phosphovorus inoculation but stable throughout the process operation. Only the minor change that four phage groups gradually became abundant after the host inoculation was observed.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.133-136
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• 2000

In recent years, hybrid neural network approaches which combine neural networks and mechanistic models have been gaining considerable interests. These approaches are potentially very efficient to obtain more accurate predictions of process dynamics by combining mechanistic and neural models in such a way that the neural network model properly captures unknown and nonlinear parts of the mechanistic model. In this work, such an approach was applied in the modeling of a full-scale coke wastewater treatment process. First, a simplified mechanistic model was developed based on the Activated Sludge Model No.1 and the specific process knowledge, Then neural network was incorporated with the mechanistic model to compensate the errors between the mechanistic model and the process data. Simulation and actual process data showed that the hybrid modeling approach could predict accurate process dynamics of industrial wastewater treatment plant. The promising results indicated that the hybrid modeling approach could be a useful tool for accurate and cost-effective modeling of biochemical processes.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.1
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• pp.19-29
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• 2020

This paper gives two graph-based algorithms for radioactive decay computation. The first algorithm identifies the connected components of the graph induced from the given radioactive decay dynamics to reduce the size of the problem. The solutions are derived over the precalculated connected components, respectively and independently. The second algorithm utilizes acyclic structure of radioactive decay dynamics. The algorithm evaluates the reachable vertices of the induced system graph from the initially activated vertices and finds the minimal set of starting vertices populating the entire reachable vertices. Then, the decay calculations are performed over the reachable vertices from the identified minimal starting vertices, respectively, with the partitioned initial value over the reachable vertices. Formal arguments are given to show that the proposed graph inspired divide and conquer calculation methods perform the intended radioactive decay calculation. Empirical efforts comparing the proposed radioactive decay calculation algorithms are presented.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.470-472
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• 2000

In this paper generation from of displacement current was compared and measured with light stimulus induce monolayers which 8A5H with azobenzene and arac.acid mixed. Light response of two monolayers which dynamics behavior are different was compared and measured though they are the same isomer The experimental results are as following; In the case of light stimulus mixed monolayers reacted less than 845H about 5[fA]. This is the mason molecule dynamic behaviour and trans was not activated due to its very chain length.

• Proceedings of the Korean Magnestics Society Conference
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• 2000.09a
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• pp.121-146
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• 2000

A novel system of magneto-optical microscope magnetometer (MOMM), capable of simultaneous local problems of magnetic properties as well as real-time magnetic domain evolution imaging of ferromagnetic thin films with 400-nm spatial resolution, New findings in domain reveral dynamics of Co-based multilayers: The reversal ratio of V/R is a governing physical parameter. The activation volumes of wall-motion and nucleation processes are generally unequal. Submicron-scale local coercivity variation determines domain reversal dynamics. A thermally activated relaxation process during domain reversal is existed on the submicron-scale in realistic films. Local variation of magnetic properties should be considered for a realistic simulation. The fantastic capabilities of the MOMM can open many possibilities to broaden and deepen our understanding of domain reversal phenomena in ferromagnetic thin films.

• Journal of Korean Neurosurgical Society
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• v.40 no.6
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• pp.434-440
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• 2006

Objective : The purpose of this study is to examine the influence of cranioplasty on dynamics of cerebral blood flow[CBF] and cerebrovascular reserve capacity[CVRC], and to investigate the usefulness of single photon emission computed tomography [SPECT] as a prognostic factor for neurological improvement after cranioplasty. Methods : Between March 2003 and December 2005, a prospective study was performed on 24 patients who had undergone total 25 cranioplasty operations. Cerebral blood flow velocities in the middle cerebral artery[MCA] and internal carotid artery[ICA] were obtained by transcranial Doppler ultrasonography[TCD]. The CVRC was assessed by SPECT in the natural state and after stimulation with 1g of acetazolamide. Neurological improvement after cranioplasty was compared between patients who showed hyperactivity to acetazolamide-activated SPECT [Group 1, n=7] and hypoactivity to acetazolamide-activated SPECT [Group 2, n=17]. These measurements were obtained two weeks prior to and two weeks after cranioplasty. Results : The blood flow velocities at the opposite site to the cranioplasty as well as at the cranioplasty site were significantly increased [P<0.05]. Compared with Group 2, there was significant increase in CBF and neurological improvement after cranioplasty in Group 1. Conclusion : Among patients with surgical bony defects, the patients who had normal reactivity of the CVRC showed a significant increase in CBF and neurological improvement after cranioplasty. The authors suggest that CVRC measurement prior to surgery may be an important prognostic factor for neurological improvement after cranioplasty.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.527-534
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• 2012

The adsorption dynamics of activated carbon (AC) and carbon molecular sieve (CMS) beds were studied to recover ethylene from FCC fuel gas. In this study, the FCC fuel gas used consisted of six-component mixture ($CH_4/C_2H_4/C_2H_6/C_3H_6/N_2/H_2$,32:15:14:2:12:25 vol.%). And the breakthrough experiments of adsorption and desorption were carried out. The breakthrough sequence in the AC bed was $H_2$ < $N_2$ < $CH_4$ < $C_2H_4$ < $C_2H_6$ while the sequence in the CMS bed was $H_2$ < $CH_4$ < $N_2$ < $C_2H_6$ < $C_2H_4$. The separation performance of the CMS bed during the adsorption step was lower than that of the AC bed. However, due to the characteristics of kinetic separation, the CMS bed could remove $CH_4/N_2$ as well asthe molecules that are larger than $C_2H_6$, which was not easy to be done by the AC bed. Since it was hard to regenerate the adsorption bed by simple depressurization, vacuum regeneration should be adopted. As a result, the pressure vacuum swing adsorption (PVSA) process, consisting of CMS pretreatment process and AC main process, was suggested to recover ethylene efficiently.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.475-483
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• 2019

Special chemical warfare agents are lethal gases that attack the human respiratory system. One of such gases are blood agents that react with the irons present in the electron transfer system of the human body. This reaction stops internal respiration and eventually causes death. The molecular sizes of these agents are smaller than the pores of an activated carbon, making chemical adsorption the only alternative method for removing them. In this study, we carried out a Computational Fluid Dynamics simulation by passing a blood agent: cyanogen chloride gas through an SG-1 gas mask canister developed by SG Safety Corporation. The adsorption bed consisted of a Silver-Zinc-Molybdenum-Triethylenediamine activated carbon impregnated with copper, silver, zinc and molybdenum ions. The kinetic analysis of the chemical adsorption was performed in accordance with the test procedure for the gas mask canister and was validated by the kinetic data obtained from experimental results. We predicted the dynamic behaviors of the main variables such as the pressure drop inside the canister and the amount of gas adsorbed by chemisorption. By using a granular packed bed instead of the Ergun equation that is used to model porous materials in Computational Fluid Dynamics, applicable results of the activated carbon were obtained. Dynamic simulations and flow analyses of the chemical adsorption with varying gas flow rates were also executed.