• Bulletin of the Korean Space Science Society
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• 2004.04a
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• pp.43-43
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• 2004

국제적인 시각비교를 위해 GPS를 이용하고 있으나, GPS 신호에는 위성까지의 거리정보뿐 아니라 위성시계, 대류층, 이온층, 다중경로 오차 등이 포함되어 있다. 그 중 이온층 지연시간을 측정하기 위해서는 Ll과 L2 반송파 신호로부터 얻어지는 P코드와 위상정보를 이용할 수 있다. 반송파 위상 정보는 P코드보다 해상도가 좋기 때문에 위상정보를 이용하게 되면 고정밀도의 이온층 지연시간을 얻게 된다. 이온층 지연시간을 통해 총전자수를 나타내는 TEC 값을 얻을 수 있는데, 관측지점으로부터 시간에 따라 가장 높은 고도의 위성을 선택하여 P코드와 반송파 위상 정보를 통한 이온층 총전자수를 파악하고 정밀도를 비교분석 하였다. (중략)

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.63-71
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• 2019

Objective: The aim of the study was to investigate the effect of zinc-bearing palygorskite (Zn-Pal) on rumen fermentation by in vitro gas-production system. Methods: In trial, 90 incubators were evenly divided into five groups: control (0% Zn-Pal), treatment I (0.2% Zn-Pal), treatment II (0.4% Zn-Pal), treatment III (0.6% Zn-Pal), and treatment IV (0.8% Zn-Pal). The contents of zinc for treatments were 0, 49, 98, 147, 196 mg/kg, respectively. The main chemical composition and microstructure of Zn-Pal was investigated by X-ray diffraction. The physicochemical features were evaluated by Zeta potential analysis, cation-exchange capacity, ethylene blue absorption and specific surface area (the Brunauer-Emmett-Teller method). In vitro gas production (GP) was recorded at 3, 6, 9, 12, 18, 24, 36, 48, 60, and 72 h incubation. Incubation was stopped at 0, 6, 12, 24, 48, and 72 h and the inoculants were tested for pH, microbial protein yield (MCP), $NH_3-N$, volatile fatty acids (VFAs), lipopolysaccharide (LPS). Results: The results showed that the GP in the treatment groups was not significantly different from the control groups (p>0.05). Compared to the control group, pH was higher at 24 h, 48 h (p<0.05), and 72 h (p<0.01) (range 6 to 7). The concentration of $NH_3-N$ in the three treatment groups was higher than in the control group at 24 h (p<0.01), meanwhile, it was lower at 48 h and 72 h (p<0.01), except in the treatment IV. The concentration of MCP in treatment I group was higher than in the control at 48 h (p<0.01). Compared with control, the LPS concentration in treatment III became lower at 12 h (p<0.05). Total VFAs in treatments were higher than in the control at 24 h, 48 h (p<0.05). Conclusion: These results suggest that the addition of Zn-Pal can improve the rumen fermentation, especially when adding 0.2% Zn-Pal.

• Journal of Environmental Health Sciences
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• v.38 no.5
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• pp.380-385
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• 2012

Background: Manganese (Mn) has been found to increase the signal intensity of the globus pallidus (GP) on T1-weighted magnetic resonance images (MRI). We performed this study in order to determine the features of liver disease that correlate with pallidal signal intensities. Methods: We assessed blood Mn levels and pallidal signals in T1-weighted MRI in 49 patients with liver cirrhosis and 23 healthy controls. Results: Increased signal intensity in the GP was observed in 30 of 49 (61.2%) patients with liver cirrhosis, with the pallidal index (PI) in patients with Child-Pugh classes B and C differing significantly from the PI in controls. Multiple linear regression analysis showed that blood Mn concentrations and Child-Pugh scores in cirrhotics were significantly associated with increased PI after controlling for other confounders (p<0.05 each). Conclusions: Pallidal signals on T1-weighted MRI are mainly observed in advanced liver cirrhosis. The present study suggests that advanced liver cirrhosis may be a human model for manganism.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.5-6
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• 2008

With the continued evolution of third-generation cellular systems and the introduction of 3GP P LTE, there is considerable progress for the new mobile wireless markets. Recently, 3GPP LTE standards are accelerated by mobile operators supporting LTE deployment and special working groups such as LSTI are working for LTE IOT and trials. In this paper, we introduce the current status of LTE activities in the mobile communications industry.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.27.2-27.2
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• 2008

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4635-4639
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• 2013

Multi-drug resistance (MDR) is an essential aspect of human lung cancer chemotherapy failure. Recent studies have shown that vinorelbine is involved in underlying processes in human tumors, reversing the MDR inseveral types of cancer cells. However, the roles and potential mechanism are not fully clear. In this study, we explored effects of vinorelbine in multi-drug resistance reversal of human lung cancer A549/DDP cells. We found that vinorelbine increased drug sensitivity to cisplatin and intracellular accumulation of rhodamine-123, while decreasing expression of P-glycoprotein (P-gp), multi-drug resistance-associated protein (MRP1) and glutathione-S-transferase ${\pi}$ (GST-${\pi}$) in A549/DDP cells. At the same time, we also established downregulation of p-Akt and decreased transcriptional activation of NF-${\kappa}B$ and twist after vinorelbine treatment. The results indicated that vinorelbine might be used as a potential therapeutic strategy in human lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4529-4532
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• 2013

Background: Acute normovolemic hemodilution (ANH) has been widely used to prevent the massive blood loss during hepatic carcinoma. The influences of ANH on coagulation function are still controversy, especially in elderly patients. The study observed ANH effects on coagulation function and fibrinolysis in elderly patients undergoing the disease. Materials and Methods: Thirty elderly patients (aged 60-70 yr) with liver cancer (ASA I or II) taken hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n=15) and control group (n=15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (130/0.4) and Ringer's solution, respectively. Blood samples were drawn from patients in both groups at five different time points: before anesthesia induction (T1), 30 min after ANH (T2), 1 h after start of operation (T3), immediately after operation (T4), and 24 h after operation (T5). Then coagulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (CD62P and activated GP IIb/GP IIIa) were measured. Results: The perioperative blood loss and allogeneic blood transfusion were recorded during the surgery. The perioperative blood loss was not significantly different between two groups (p>0.05), but the volume of allogeneic blood transfusion in ANH group was significantly less than in control group ($350.0{\pm}70.7$) mL vs. ($457.0{\pm}181.3$) mL (p<0.01). Compared with the data of T1, the prothrombin time (PT) and activated partial thromboplastin time (APTT) measured after T3 were significantly longer (p<0.05) in both groups, but within normal range. There were no significant changes of thrombin time (TT) and D-dimer between two groups at different time points (p>0.05). SFMC and F1+2 increased in both groups, but were not statistically significant. PAC-1-positive cells and CD62P expressions in patients of ANH group were significantly lower than those at T1 (p<0.05) and T2-T5 (p>0.05). Conclusions: ANH has no obvious impact on fibrinolysis and coagulation function in elderly patients undergoing resection of liver cancer. The study suggested that ANH is safe to use in elderly patients and it could reduce allogeneic blood transfusion.

• Advances in pediatric surgery
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• v.17 no.2
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• pp.170-178
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• 2011

Hiatal hernia is a very rare disease in the pediatric population. However information from our esophageal atresia postoperative follow-up program has hypotheses; "Hiatal hernia may more frequently occur in postoperative esophageal atresia patients (EA group) than in the general pediatric population (GP group)" and "The tension on the esophagus after esophageal anastomosis may be an important etiologic factor of hiatal hernia in EA group". To prove the first hypotheses, we compared the incidence of hiatal hernia in the GP group with the incidence in the EA group. The Incidence in the GP group was obtained from national statistic data from Statistics Korea and Health Insurance Review and Assessment Service of Korea. The incidence in the EA group was obtained from the medical record and the imaging studies of our esophageal atresia postoperative follow-up program. To prove the second hypothesis, the presumptive risk factors for the development of hiatal hernia in EA group, such as the type of esophageal atresia, degree of esophageal gap, the stage operation and the redo-operation with resection and re-anastomosis of esophagus were analyzed statistically. The total number of patients in the EA group was ninety-nine and there were 5 hiatus hernias. The incidence of EA group (5 %) is significantly higher than incidence of GP group (0.024 %). (p=0.0001) The statistical analysis of the presumptive risk factors for hiatal hernia development in EA group failed to show any evidence of correlation between postoperative esophageal tension and the hiatal hernia. This study shows that the postoperative patients with esophageal atresia have high occurrence of hiatal hernia and should be followed up carefully to detect hiatal hernia.

• Food Science and Preservation
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• v.5 no.3
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• pp.247-255
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• 1998

This study was carried out to investigate changes in the flesh firmness, evolution of ethylene, cell wall components, and degradation and solubilization of polyuronide(PU) and polysaccharide(PS) in green(GP) and mature persimmon(MP) fruits according to testing time of ethylene(50${\mu}\ell$ㆍL$^{-1}$ ). When ethylene was treated in GP and MP, flesh firmness rapidly decreased and it was decreased more GP than MP. When ethylene were treated for 12 hours in GP, production of ethylene began after 3 days. The amount of ethylene product was maximum 16,000 ${\mu}\ell$ㆍL$^{-1}$ at 24 hours of ethylene treatment. However, ethylene was not producted until 7 days after 24 hours ethylene treatment at MP. The content of pectic substances decreased in the distilled- water, 0.05M $Na_2$CO$_3$,4M and 8M KOH-soluble fractions during softening according to increasing time of ethylene treatment. Arabinose and galactose were the major non-cellulosic neutral sugars in the 0.05M CDTA and 0.05M $Na_2$CO$_3$-soluble pectic fractions. Glucose, galactose and xylose were the major non-cellulosic neutral sugars in the 4M KOH- soluble hemicellulosic fraction. High molecular of PU and PS were degraded and solubilized in the distilled-water, 0.05M CDTA 0.05M $Na_2$CO$_3$ and 4M KOH-soluble fractions during time of ethylene treatment.

• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.735-740
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• 2002

In order to improve the anti-fogging property of polymer films, organic-inorganic hybrid coating solutions which have good hydrophilic property and transmission in the range of visible light were synthesized by the sol-gel method. The coating solutions were prepared by adding glycidoxypropyl trimethoxysilane(GPS) to a colloidal silica(15 nm) suspension(Ludox). GPS as silane coupling agent forms strong bonds to the colloidal silica and surrounding polymer matrix and links two different materials together. Solutions prepared by addition of GPS at the acidic condition resulted in coatings that were less prone to cracking, while those at the basic condition caused coatings with more cracking. These resulted in better hydrophilic property and transmission in the range of visible light for the solution prepared at the acidic condition(pH 2). Compared with coatings under acidic conditions, coatings prepared at basic conditions showed worse hydrophilic property and transmission in the range of visible light.