• Membrane Journal
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• v.21 no.2
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• pp.201-211
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• 2011

The effects of humic acid (HA), photo-oxidation and adsorption were investigated in hybrid process of ceramic ultrafiltration and photocatalyst for drinking water treatment. UF, photocatalyst, and UV radiation processes were investigated in viewpoints of membrane fouling resistance $(R_f)$, permeate flux (J), and total penneate volume $(V_{\Upsilon})$ at 2 and 4 mg/L of HA respectively. As decreasing HA, $R_f$ decreased dramatically and J increased, and finally $V_{\Upsilon}$ was the highest at 2 mg/L HA. Average treatment efficiencies of turbidity decreased as increasing HA, but treatment efficiency of HA was the highest at 4 mg/L HA. It was because most of HA was removed by membrane and some HA passing through the membrane was adsorbed or photo-oxidized by photocatalyst at low HA, and therefore treated water quality was almost same at 2 and 4 mg/L HA, but feed water quality was higher at 4 mg/L. At effect experiment of photo-oxidation and adsorption, J of UF + $TiO_2$ + UV process was maintained at the highest, and ultimately $(V_{\Upsilon})$ after 180 minutes' operation was the highest. As results of comparing the treatment efficiencies of turbidity and HA, photocatalyst adsorption had more important role than photo-oxidation when HA increased from 2 to 4 mg/L.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.780-803
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• 2003

Exposure of skin cells, particularly keratinocytes to various nuclear factor-kappaB ($\textrm{NF}_{-{\kappa}}\textrm{B}$) activators [e.g. tumor necrosis factor-$\alpha$, interleukin-1, lipopolysaccharides, and ultraviolet light] leads to phosphorylation and degradation of the inhibitory protein, $\textrm{I}_{{\kappa}}\textrm{B}$. Liberated $\textrm{NF}_{-{\kappa}}\textrm{B}$ is translocated into the nucleus where it can change or alter expression of target genes, resulting in the secretion of extracellular signaling molecules including melanotrophic factors affecting melanocyte. In order to demonstrate the possible role of $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation on the synthesis of melanotrophic factors from the keratinocytes, the activities of $\textrm{NF}_{-{\kappa}}\textrm{B}$ induced by melanogenic inhibitors (MIs) were determined in human HaCaT keratinocytes transfected with $\textrm{pNF}_{-{\kappa}}\textrm{B}$-SEAP-NPT plasmid. Transfectant cells released the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the $\textrm{NF}_{-{\kappa}}\textrm{B}$ activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selection marker for geneticin resistance. MIs such as niacinamide, kojic acid, hydroquinone, resorcinol, arbutin, and glycolic acid were preincubated with transfectant HaCaT cells for 3 h and then ultraviolet B (UVB) was irradiated. $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation was measured with the SEAP reporter gene assay using a fluorescence detection method. Of the Mis tested, kojic acid ($IC_{50}$/ = 60 $\mu$M) was found to be the most potent inhibitor of UVB-upregulating $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation in transfectant HaCaT cells, which is followed by niacinamide ($IC_{50}$/= 540 $\mu$M). Pretreatment of the transfectant HaCaT cells with the Mis, especially kojic acid and niacinamide, effectively lowered $\textrm{NF}_{-{\kappa}}\textrm{B}$ binding measured by electrophoretic mobility shift assay. Furthermore, these two inhibitors remarkably reduced the secretion level of IL-6, one of melanotrophic factors, triggered by UV-radiation of the HaCaT cells. These observations suggest that Mis working at the in vivo level might act partially through the modulation of the synthesis of melanotrophic factors in keratinocyte.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.250-255
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• 2007

The RecA protein of Deinococcus radiodurans is essential for the extreme radiation resistance of this organism. The central steps involved in recombinational DNA repair require DNA-dependent ATP hydrolysis by recA protein. Key feature of RecA protein-mediated activities is the interactions with ssDNA and dsDNA. The ssDNA is the site where RecA protein filament formation nucleates and where initiation of DNA strand exchange takes place. The effect of sequence heterogeneity of ssDNA was examined in this experiment. The rate of homopolymeric synthetic ssDNA-dependent ATP hydrolysis was constant or nearly so over a broader range of pHs. For poly(dT)-dependent ATP or dATP hydrolysis, rates were generally faster, with a broader optimum between pH 7.0 and 8.0. Activities of RecA protein were affected by the ionic environment. The ATPase activity was shown to have different sensitivity to anionic species. The presence of glutamate seemed to slimulate the hydrolytic activity. Dr RecA protein was shown to require $Mg^{2+}$ ion greater than 2 mM for binding to etheno ssDNA and the binding stoichiometry of 3 nucleotide for RecA protein monomer.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.69-78
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• 2003

In this study, the energy conversion equipment from the radiation energy to mechanical energy by using n­pentane as the operating fluid was constructed and the performance to pump the water was tested for the utilization of solar powered water pump. The equipment was designed optimally, after the theoretical analyses of the water pumping head and water quantity per cycle were done. The pentane vapour temperature in the condenser and the temperature of the outlet water from the condenser became lowered and the heat transfer rate became higher with decreasing the water inlet level to the condenser. The temperature difference between the condenser and the water tank was significant. Therefore, the distance between the water tank and condenser was recommended to be shorten and the diameter of their connecting pipe was recommended to be narrow in order to reduce the resistance of the fluid passage and improve the heat transfer rate. The amount of water pumped was 1.6­2.4 liters. Mass flow rate of the cooling water became lowered when the cooling water pipe was prolonged from the condenser to improve the heat transfer rate.

• Journal of the Korean Magnetics Society
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• v.15 no.3
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• pp.202-206
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• 2005

The present investigation provides an electromagnetic radiation absorptive composition which comprises silver-coated ferrite microspheres dispersed in silicon rubber matrix for the aim of thin microwave absorber in GHz frequencies. Ni-Zn ferrite spheres with $50{\mu}m$ size in average were prepared by spray-drying and sintering at $1130^{\circ}C$. Conductive silver layer was plated on ferrite spheres by electroless plating. Conductive Ni-Zn ferrite sphere with uniform silver layer were obtained in the concentration of 10 g/L $AgNO_3$ per 20 g ferrite spheres. For this powder, electrical resistance is reduced as low as $10^{-2}\~10^{-3}\;\Omega$. The most sensitive material parameters with silver plating is real and imaginary parts of complex permittivity. The conductive Ni-Zn ferrite spheres have large values of dielectric constant. Due to this high dielectric constant of microspheres, matching thickness is reduced to as low as 2 mm at the frequency of 7 GHz, which is much thinner than conventional ferrite absorbers.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5691-5696
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• 2014

Background: Many clinical trials have been conducted to evaluate sorafenib for the treatment of advanced NSCLC, but the results for efficacy have been inconsistent. The aim of this study was to evaluate the efficacy and safety of sorafenib in patients with advanced NSCLC in more detail by meta-analysis. Methods: This meta-analysis of randomized controlled trials (RCTs) was performed after searching PubMed, EMBASE, ASCO Abstracts, ESMO Abstracts, and the proceedings of major conferences for relevant clinical trials. Two reviewers independently assessed the quality of the trials. Outcomes analysis were disease control rate (DCR), progression- free survival (PFS), overall survival (OS) with 95% confidence intervals (CI) and major toxicity. Subgroup analysis was conducted according to sorafenib monotherapy, in combination with chemotherapy or EGFR-TKI to investigate the preferred therapy strategy. Results: Results reported from 6 RCTs involving 2, 748 patients were included in the analysis. Compared to sorafenib-free group, SBT was not associated with higher DCR (RR 1.31 (0.96- 1.79), p=0.09), PFS (HR 0.82 (0.66-1.02), p=0.07) and OS (HR 1.01 (0.92-1.12), p=0.77). In terms of subgroup results, sorafenib monotherapy was associated with significant superior DCR and longer PFS, but failed to show advantage with regard to OS. Grade 3 or greater sorafenib-related adverse events included fatigue, hypertension, diarrhea, oral mucositis, rash and HFSR. Conclusions: SBT was revealed to yield no improvement in DCR, PFS and OS. However, sorafenib as monotherapy showed some activity in NSCLC. Further evaluation may be considered in subsets of patients who may benefit from this treatment. Sorafenib combined inhibition therapy should be limited unless the choice of platinum-doublet regimen, administration sequence or identification of predictive biomarkers are considered to receive better anti-tumor activity and prevention of resistance mechanisms.

• Biomolecules & Therapeutics
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• v.21 no.1
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• pp.29-34
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• 2013

The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor family of cytokines. TRAIL selectively induces apoptotic cell death in various tumors and cancer cells, but it has little or no toxicity in normal cells. Agonism of TRAIL receptors has been considered to be a valuable cancer-therapeutic strategy. However, more than 85% of primary tumors are resistant to TRAIL, emphasizing the importance of investigating how to overcome TRAIL resistance. In this report, we have found that nemadipine-A, a cell-permeable L-type calcium channel inhibitor, sensitizes TRAIL-resistant cancer cells to this ligand. Combination treatments using TRAIL with nemadipine-A synergistically induced both the caspase cascade and apoptotic cell death, which were blocked by a pan caspase inhibitor (zVAD) but not by autophagy or a necrosis inhibitor. We further found that nemadipine-A, either alone or in combination with TRAIL, notably reduced the expression of survivin, an inhibitor of the apoptosis protein (IAP) family of proteins. Depletion of survivin by small RNA interference (siRNA) resulted in increased cell death and caspase activation by TRAIL treatment. These results suggest that nemadipine-A potentiates TRAIL-induced apoptosis by down-regulation of survivin expression in TRAIL resistant cells. Thus, combination of TRAIL with nemadipine-A may serve a new therapeutic scheme for the treatment of TRAIL resistant cancer cells, suggesting that a detailed study of this combination would be useful.

• Journal of Korea Water Resources Association
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• v.45 no.6
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• pp.557-568
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• 2012

In order to understand the hydrological processes on the mountainous forest, the configuration of soil evaporation (E) out of evapotranspiration (ET) is a challenging and important topic. In this study, we attempted to understand the soil evaporation process for a humid forest hillslope via measuring and analyzing soil moistures with a sampling interval in 2 hours at three locations for 10 days between May 22th and 31th 2009. Two methods were used to estimate soil evaporation in every 2hr; one is a method using soil moisture measurement ($E_{SM}$), the others methods are based on Penman equation (Penman (1948), Staple (1974), Konukcu (2007), Equilibrium Penman ($E_{equili}$)). As a critical parameter in determining $E_{SM}$, the dry surface layer (DSL), was estimated using energy balance equation. The accumulated soil evaporation ($E_{SM}$) of A, B, C points were estimated as 2.09, 1.08 and 2.88 mm, respectively. The estimated evaporation of Penman (1948), Staple (1974), Konukcu (2007), $E_{equili}$ were 4.91, 8.80, 8.63 and 3.28 mm. The proposed method with soil moisture measurement showed lower soil evaporations than the other conventional methods. The increasing soil temperature and interaction between soil and atmosphere due to existence of litter and DSL are considered as dominant factors for soil evaporation. The $E_{SM}$ has the apparent lag time between 2 and 4 hr compared with $E_{equili}$ and net radiation. The DSL and surface resistance ($r_s$) were increased as soil moisture was decreased for in this study. The estimated DSL through the temporal distribution analysis of soil moisture and tension measurements was also similar to that of the energy balance relationship.

• Archives of Plastic Surgery
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• v.44 no.6
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• pp.516-522
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• 2017

Background Implant-based breast reconstruction is being performed more frequently, and implants are associated with an increased risk of infection. We reviewed the clinical features of cases of implant infection and investigated the risk factors for breast device salvage failure. Methods We retrospectively analyzed 771 patients who underwent implant-based breast reconstruction between January 2010 and December 2016. Age, body mass index, chemotherapy history, radiation exposure, and smoking history were assessed as potential risk factors for postoperative infection. We also evaluated the presence and onset of infection symptoms, wound culture pathogens, and other complications, including seroma, hematoma, and mastectomy skin necrosis. Additionally, we examined the mastectomy type, the use of acellular dermal matrix, the presence of an underlying disease such as hypertension or diabetes, and axillary node dissection. Results The total infection rate was 4.99% (58 of 1,163 cases) and the total salvage rate was 58.6% (34 of 58). The postoperative duration to closed suction drain removal was significantly different between the cellulitis and implant removal groups. Staphylococcus aureus infection was most frequently found, with methicillin resistance in 37.5% of the cases of explantation. Explantation after infection was performed more often in patients who had undergone 2-stage expander/implant reconstruction than in those who had undergone direct-to-implant reconstruction. Conclusions Preventing infection is essential in implant-based breast reconstruction. The high salvage rate argues against early implant removal. However, when infection is due to methicillin-resistant S. aureus and the patient's clinical symptoms do not improve, surgeons should consider implant removal.

• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1273-1279
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• 2016

Production of iodine-131 by neutron activation of tellurium in tellurium dioxide ($TeO_2$) material requires a target that meets the safety requirements. In a radiopharmaceutical production unit, a new lid for a can was designed, which permits tight sealing of the target by using tungsten inert gaswelding. The leakage rate of all prepared targets was assessed using a helium mass spectrometer. The accepted leakage rate is ${\leq}10^{-4}mbr.L/s$, according to the approved safety report related to iodine-131 production in the TRIGA Mark II research reactor (TRIGA: Training, Research, Isotopes, General Atomics). To confirm the resistance of the new design to the irradiation conditions in the TRIGA Mark II research reactor's central thimble, a study of heat effect on the sealed targets for 7 hours in an oven was conducted and the leakage rates were evaluated. The results show that the tightness of the targets is ensured up to $600^{\circ}C$ with the appearance of deformations on lids beyond $450^{\circ}C$. The study of heat transfer through the target was conducted by adopting a one-dimensional approximation, under consideration of the three transfer modes-convection, conduction, and radiation. The quantities of heat generated by gamma and neutron heating were calculated by a validated computational model for the neutronic simulation of the TRIGA Mark II research reactor using the Monte Carlo N-Particle transport code. Using the heat transfer equations according to the three modes of heat transfer, the thermal study of I-131 production by irradiation of the target in the central thimble showed that the temperatures of materials do not exceed the corresponding melting points. To validate this new design, several targets have been irradiated in the central thimble according to a preplanned irradiation program, going from4 hours of irradiation at a power level of 0.5MWup to 35 hours (7 h/d for 5 days a week) at 1.5MW. The results showthat the irradiated targets are tight because no iodine-131 was released in the atmosphere of the reactor building and in the reactor cooling water of the primary circuit.