• Journal of Korean Society for Atmospheric Environment
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• v.24 no.1
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• pp.30-42
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• 2008

In this study, the chemical compositions of $PM_{2.5}$ samples collected at the Redwood National Park IMPROVE site in California from March 1988 to May 2004 were analyzed to provide source identification and apportionment. A total of 1,640 samples were collected and 33 chemical species were analyzed by particle induced X-ray emission, proton elastic scattering analysis, photon induced X-ray fluorescence, ion chromatography, and thermal optical reflectance methods. Positive matrix factorization (PMF) was used to develop source profiles and to estimate their mass contributions. The PMF modeling identified five sources and the average mass was apportioned to motor vehicle (35.8%, $1.58\;{\mu}g/m^3$), aged sea salt (23.2%, $1.02\;{\mu}g/m^3$), fresh sea salt (21.4%, $0.94\;{\mu}g/m^3$), wood/field burning (16.1%, $0.71\;{\mu}g/m^3$), and airborne soil (3.5%, $0.15\;{\mu}g/m^3$), respectively. To analyze local source impacts from various wind directions, the CPF and NPR analyses were performed using source contribution results with the wind direction values measured at the site. These results suggested that sources of $PM_{2.5}$ are also sources of visibility degradation and then source apportionment studies derived for $PM_{2.5}$ are also used for understanding visibility problem.

• 한국해양학회지
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• v.5 no.1
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• pp.30-36
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• 1970

The water quality of the laver bed at Yongwon Ri, Changwon Gun was investigated during the spring and neap tide in March 1970. The effect of tide on the contents of various chemical constituents was irregular and the variation ranges of the contents were narrow. The pH value during flood and ebb tide was a constant of 8.2. The chlorosity range varied from 19.15 to 19.33g/l, the difference of 0.18g/l being comparatively small for coastal waters. The nutrient salts contents varied irregulary with the change in tide, but nitrite and soluble iron were not detected. In local distribution, chlorosity and silicate- silicon contents were found to be more at Sts. 1, 2 and 3 in the eastern area than at Sts. 4, 5 and 6 in the western area, wheras nitrate and ammonia contents were found to be more at Sts. 4, 5 and 6. The nitrate content was especially high, being twice as much as that at Sts. 1, 2 and 3 in the eastern area. In the spring tide, chlorosity was found, on the average, to be as much as 0.06g/l higher than in the neap tide, but the contents of nutrient salts were higher in the neap tide, especially the nitrate content was twice as much. When compared with other selected local laver beds, i.e., the tidal flats of the Nackdong and Somjin rivers, and of Wan Do Gun, the chlorosity level was highest but the nutrient salts contents level was, in general, slightly lower and the variation ranges narrow in the laver bed at Yongwon ri. The nitrate content, in particular was one tenth smaller than the others.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.797-802
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• 2015

Background: The purpose of this study was to prospectively evaluate the predictive value of perfusion computed tomography (CT) for response of local advanced esophageal carcinoma to radiotherapy and chemotherapy. Materials and Methods: Before any treatment, forty-three local advanced esophageal squamous cell carcinomas were prospectively evaluated by perfusion scan with 16-row CT from June 2009 to January 2012. Perfusion parameters, including perfusion (BF), peak enhanced density (PED), blood volume (BV), and time to peak (TTP) were measured using Philips perfusion software. Seventeen cases received definitive radiotherapy and 26 received concurrent chemo-radiotherapy. The response was evaluated by CT scan and esophagography. Differences in perfusion parameters between responders and non-responders were analyzed, and ROCs were used to assess predictive value of the baseline parameters for treatment response. Results: There were 25 responders (R) and 18 non-responders (NR). Responders showed significantly higher BF (R:34.1 ml/100g/min vs NR: 25.0 ml/100g/min, p=0.001), BV (23.2 ml/100g vs 18.3 ml/100g, p=0.009) and PED (32.5 HU vs 28.32HU, P=0.003) than non-responders. But the baseline TTP (R: 38.2s vs NR: 44.10s, p=0.172) had no difference in the two groups. For baseline BF, a threshold of 36.1 ml/100g/min achieved a sensitivity of 56%, and a specificity of 94.4% for detection of clinical responders from non-responders. Conclusions: The results suggest that the perfusion CT can provide some helpful information for identifying tumors that may respond to radio-chemotherapy.

• Plant Biotechnology Reports
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• v.2 no.1
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• pp.41-46
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• 2008

Salinity stress is a major limiting factor in cereal productivity. Many studies report improvements in salt tolerance using model plants, such as Arabidopsis thaliana or standard varieties of rice, e.g., the japonica rice cultivar Nipponbare. However, there are few reports on the enhancement of salt tolerance in local rice cultivars. In this work, we used the indica rice (Oryza sativa) cultivar BR5, which is a local cultivar in Bangladesh. To improve salt tolerance in BR5, we introduced the Escherichia coli catalase gene, katE. We integrated the katE gene into BR5 plants using an Agrobacterium tumefaciens-mediated method. The introduced katE gene was actively expressed in the transgenic BR5 rice plants, and catalase activity in $T_1$ and $T_2$ transgenic rice was approximately 150% higher than in nontransgenic plants. Under NaCl stress conditions, the transgenic rice plants exhibited high tolerance compared with nontransgenic rice plants. $T_2$ transgenic plants survived in a 200 mM NaCl solution for 2 weeks, whereas nontransgenic plants were scorched after 4 days soaking in the same NaCl solution. Our results indicate that the katE gene can confer salt tolerance to BR5 rice plants. Enhancement of salt tolerance in a local rice cultivar, such as BR5, will provide a powerful and useful tool for overcoming food shortage problems.

• Bulletin of the Korean Mathematical Society
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• v.53 no.5
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• pp.1341-1352
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• 2016

Let R be a commutative Noetherian ring, ${\Phi}$ a system of ideals of R and $I{\in}{\Phi}$. In this paper among other things we prove that if M is finitely generated and $t{\in}\mathbb{N}$ such that the R-module $H^i_{\Phi}(M)$ is $FD_{{\leq}1}$ (or weakly Laskerian) for all i < t, then $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all i < t and for any $FD_{{\leq}0}$ (or minimax) submodule N of $H^t_{\Phi}(M)$, the R-modules $Hom_R(R/I,H^t_{\Phi}(M)/N)$ and $Ext^1_R(R/I,H^t_{\Phi}(M)/N)$ are finitely generated. Also it is shown that if cd I = 1 or $dimM/IM{\leq}1$ (e.g., $dim\;R/I{\leq}1$) for all $I{\in}{\Phi}$, then the local cohomology module $H^i_{\Phi}(M)$ is ${\Phi}$-cofinite for all $i{\geq}0$. These generalize the main results of Aghapournahr and Bahmanpour [2], Bahmanpour and Naghipour [6, 7]. Also we study cominimaxness and weakly cofiniteness of local cohomology modules with respect to a system of ideals.

• Korean Journal of Head & Neck Oncology
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• v.15 no.1
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• pp.29-34
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• 1999

Objectives: This study was carried out to analyze the clinical profile and the results of treatment of a series of patients with extramedullary plasmacytoma(EMP) of the head and neck. Materials and Methods: The clinical features, treatment and survival of 14 patients with EMP seen at Yonsei Medical Center between 1970 and 1998 were carefully reviewed. Results: The median age was 48 years(range 15-75) and there was a male predominance(M:F 1.8:1). Nasal cavities and paranasal sinuses account for 50% of the primary sites and the most common symptom was airway obstruction(50%). Five patients(36%) showed evidence of adjacent bone destruction, one patient had lymph node involvement and one patient had an IgG monoclonal gammopathy at the time of diagnosis. All 5 patients treated with radiotherapy alone achieved local control. Of 5 patients treated with surgery alone, 2 patients(40%) had local failure. Of 3 patient treated with a combination of surgery and radiotherapy, one patient had local recurrence. A total of7 patients(54%) had local, distant or nodal relapses after primary treatment. Six of them received salvage treatment. With salvage treatment of surgery and/or radiotherapy, local control was achieved in 4 of 6 patients. Conversion to multiple myeloma was seen in one patient. Conclusion: Radiotherapy should be recommanded as treatment of choice for EMP of the head and neck. Surgery should be reserved for radioresistant or recurrent tumors, but tumors that are localized and can be removed relatively easily with little morbidity may be treated by primary surgery.

• Analytical Science and Technology
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• v.19 no.5
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• pp.415-421
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• 2006

The following concentrations of some PAHs were investigated; [benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, indeno (1,2,3-c,d)pyrene] in vegetables(n=160) and fruits(n=50). The food samples were purchased at the local markets in Seoul, Chuncheon, Daejeon, Kwangju and Pusan. The samples were radish, onion, bean sprouts, welsh onion, chinese cabbage, spinach, young pumpkin, garlic, cucumber, carrot, lettuce, sesame leaf, tangerine, persimmon, apple, pear and banana. The methodology involved ultrasonic extraction with dichloromethane, clean-up on Sep-Pak florisil cartridges and determination by HPLC/FLD (High Performance Liquid Chromatography/Fluorescence Detector). Overall method recoveries for 8 PAHs spiked into these products ranged from 95 to 102%. The mean level of the following PAHs were determined; benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene and indeno(1,2,3-c,d)pyrene in vegetables and fruits was N.D., 0.014 ng/g, 0.031 ng/g, 0.016 ng/g, 0.019 ng/g, 0.091 ng/g, 0.016 ng/g and N.D., respectively.

• Journal of IKEEE
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• v.27 no.1
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• pp.109-115
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• 2023

In this paper, we design and implement an Ultra-Wide Band (UWB, 3.1~10.6 GHz) antenna with 5G mobile communication (3.42~3.70 GHz) and Wireless Local Area Network (WLAN, 5.15~5.825 GHz) bands rejection characteristics. The proposed antenna consists of a planar radiation patch with two slots. The upper slot contributes to reject 5G mobile communication band and the lower slot contributes to reject WLAN band. The Voltage Standing Wave Ratio (VSWR) values of the proposed antenna show good performances in whole UWB band except for rejection bands based on VSWR 2.0. The proposed UWB antenna was simulated using High Frequency Struture Simulator (HFSS) by Ansoft. The simulated antenna showed dual rejection bands of 3.31~3.92 GHz and 5.04~5.90 GHz in UWB band, and measured antenna showed dual rejection bands of 3.35~3.97 GHz and 5.06~5.97 GHz. The largest VSWR values measured at each rejection band are 13.60 at 3.64 GHz and 10.25 at 5.52 GHz. The measured maximum gain is 5.31 dBi at 10.00 GHz. The lowest gains for the measured antenna at rejection bands are -8.73 dBi at 3.70 GHz and -4.36 dBi at 5.56 GHz.

• Journal of Periodontal and Implant Science
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• v.43 no.3
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• pp.121-129
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• 2013

Purpose: The present study has two aims; firstly, it attempts to verify the presence of oxidative stress by estimating the reactive oxygen species (ROS) levels in periodontal pockets ${\geq}5$ mm as compared to controls. The second aim is to evaluate the effect of lycopene as a locally delivered antioxidant gel on periodontal health and on the gingival crevicular fluid (GCF) levels of 8-hydroxydeoxyguanosine (8-OHdG), a marker of oxidative injury. Methods: Thirty-one subjects participated in this study. In the pretreatment phase, the ROS levels in pockets ${\geq}5$ mm were measured by flow cytometry. Three sites in each subject were randomly assigned into each of the following experimental groups: sham group, only scaling and root planing (SRP) was done; placebo group, local delivery of placebo gel after SRP; and lycopene group, local delivery of lycopene gel after SRP. Clinical parameters included recording site-specific measures of GCF 8-OHdG, plaque, gingivitis, probing depth, and clinical attachment level. Results: The gel, when delivered to the sites with oxidative stress, was effective in increasing clinical attachment and in reducing gingival inflammation, probing depth, and 8-OHdG levels as compared to the placebo and sham sites. Conclusions: From this trial conducted over a period of 6 months, it was found that locally delivered lycopene seems to be effective in reducing the measures of oxidative stress and periodontal disease.

• Korean Journal of Pharmacognosy
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• v.40 no.1
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• pp.6-12
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• 2009

Thirty five methanol extracts from 19 natural local plants, which have been used as traditional anti-cancer medicine, were prepared. They were analyzed the cytotoxic effects on primary fibroblast cells and carcinoma cells. The root extract of Solanum nigrum were highly toxic in both cell lines with $IC_{50}$ values of less than $0.01{\mu}g/{\mu}l$, and 26 of 35 extracts were toxic in all cells with $IC_{50}$ values of $0.1{\sim}2{\mu}g/{\mu}l$. Three extracts including the fruit extracts of Solanum nigrum and Morus alba had no cytotoxic activity in both cell lines. Five of 35 extracts were highly toxic in cancer cells than in primary cells. Because primary cells were more resistant on these extracts, the five extracts were selected for anti-cancer agent candidates. Apoptosis or programmed cell death has an essential role in chemotherapy-induced tumor cell killing. Recently, inducers of apoptosis have been used in cancer therapy. When two of 5 cancer cell-specific cytotoxic extracts (Ulmus parvifolia and Zelkova serrata) were treated in concentration of $0.02{\sim}0.1{\mu}g/{\mu}l$, apoptosis were increased at 3-5 times in cancer cell lines. Finally, the apoptotic effects of these extracts were confirmed by cleavages of both poly-(ADP-ribose)-polymerase and caspase-3 as apoptotic markers. In this report, we suggested that two of 35 medicinal herb extracts can be useful anti-cancer drug candidates inducing apoptosis in several carcinoma cell lines.