• Bulletin of the Korean Chemical Society
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• v.15 no.5
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• pp.379-386
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• 1994

Reactions of 1',2-bis(diphenylphosphino)-l-(N,N-dimethylaminomethyl)ferrocene (FcNPP) with $M(CO)_6$ (M=Cr, Mo, W) in the presence of TMNO (Trimethylamine oxide) in a stoichiometric ratio of 1 : 1.5 : 3.5 produced a series of Gp 6 metal carbonyl derivatives with a variety of coordination modes: M(CO)$_4({\eta}^2$-FcNPP-P,P) (M=Cr, Mo, W), $M(CO)_5({\eta}^1-FcNPP-P) (M=Mo, W)\;,\; M_2(CO)_9({\eta}^1\;,\;{\eta}^2-FcNPP-P,P,N) (M=Cr, Mo)\;,\;M_2(CO)_{10}({\eta}^1\;,\;{\eta}^1-FcNPP-P,P) (M=Cr, Mo, W)\;, and\;W(CO)_4({\eta}^2-FcNPP(O)-P,N)$. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of W(CO)$_4({\eta}^2$-FcNPP(O)-P,N) was determined by X-ray crystallography. Crystals are monocinic, space group P$2_{1/C}$, with a=10.147(2), b=19.902(3), c=19.821(4) ${\AA},\;{\beta}=96.88(2)^{\circ},\;V=3974(l){\AA}^3$, Z=4, and $D_{calc}=1.64 g cm^{-3}$. The geometry around the central tungsten metal is a distorted octahedron, with the nitrogen and phosphorus atoms being cis to each other. Some of these complexes exhibited catalytic activities in the allylic oxidation and epoxidation of cholesterly acetate. Other oxidation products were also formed with the different chemical yields and product distribution depending upon the ligand and the central metal.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.442-450
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• 2015

This study was conducted to investigate the effect of Psy-2A-CrtI (PAC), a genetically modified (GM) rice with enhanced ${\beta}$-carotene, on the soil microbial community. The soil used to cultivate GM rice and its wild-type, Nakdong, was analyzed for population density, denaturing gradient gel electrophoresis (DGGE), and pyrosequencing. It was found that the bacterial, fungal and actinomycetes population densities of the PAC soils were within the range of those of the non-GM rice cultivar, Nakdong. The DGGE banding patterns of the GM and non-GM soils were also similar, suggesting that the bacterial community structures were stable within a given month and were unaffected by the presence of a GM plant. The pyrosequencing result showed a temporal difference in microorganism taxon and distribution ratio, but no significant difference between GM and non-GM was found. The persistence of the transgene DNA in the plant and surrounding soil were investigated for different time periods. There were differences in the persistence within the plant depending on the gene, but they could not be detected after 5 weeks. Also the transgenes were not detected in the surrounding soil. These results indicate that soil microbial communities are unaffected by the cultivation of a PAC rice within the experimental time frame.

• Earthquakes and Structures
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• v.17 no.2
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• pp.163-173
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• 2019

For Special Concentrically Braced Frame (SCBF), it is common that the damage concentrates at a certain story instead of spreading over all stories. Once the damage occurs, the soft-story mechanism is likely to take place and possibly to result in the failure of the whole system with more damage accumulation. In this study, we use a strongback column which is an additional structural component extending along the height of the building, to redistribute the excessive deformation of SCBF and activate more structural members to dissipate energy and thus avoid damage concentration and improve the seismic performance of SCBF. We tested one-third-scaled, three-story, double-story X SCBF specimens with static cyclic loading procedure. Three specimens, namely S73, S42 and S0, which represent different combinations of stiffness and strength factors ${\alpha}$ and ${\beta}$ for the strongback columns, were designed based on results of numerical simulations. Specimens S73 and S42 were the specimens with the strongback columns, and S0 is the specimen without the strongback column. Test results show that the deformation distribution of Specimen S73 is more uniform and more brace members in three stories perform nonlinearly. Comparing Drift Concentration Factor (DCF), we can observe 29% and 11% improvement in Specimen S73 and S42, respectively. This improvement increases the nonlinear demand of the third-story braces and reduces that of the first-story braces where the demand used to be excessive, and, therefore, postpones the rupture of the first-story braces and enhances the ductility and energy dissipation capacity of the whole SCBF system.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.505-513
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• 2021

Objective : The adaptive immune response following subarachnoid hemorrhage (SAH) is not well understood. We evaluated and compared the T cell receptor (TCR) immune repertoire of good-grade and poor-grade SAH patients to elucidate the T cell immunology after ictus. Methods : Peripheral blood from six SAH patients was collected at two different times, admission and at the 7-day follow-up. Composition and variation of the TCR β-chain (TCRB) complimentary determining regions (CDR) 3 repertoire was examined using high-throughput sequencing; the analysis was based on sampling time and disease severity (good vs. poor-grade SAH). Results : Clonality at admission and follow-up were 0.059 (0.037-0.038) and 0.027 (0.014-0.082) (median, 25th-75th percentile). Poor-grade SAH (0.025 [0.011-0.038]) was associated with significantly lower clonality than good-grade SAH (0.095 [0.079-0.101]). Poor-grade SAH patients had higher diversity scores than good-grade SAH patients. CDR length was shorter in good-grade SAH vs. poor-grade SAH. Differences in clonotype distribution were more prominent in TCRBV gene segments than TCRBJ segments. TCRBV19-01/TCRBJ02-04 and TCRBV28-01/TCRBJ02-04 were the most increased and the most decreased V-J pairs in the 7-day follow-up compared to admission in good-grade SAH. The most increased and decreased V-J pairs in poor-grade SAH patients were TCRBV28-01/TCRBJ02-06 and TCRBV30-01/TCRBJ02-04, respectively. Conclusion : The TCRB repertoire is dynamic in nature following SAH. TCRB repertoire may facilitate our understanding of adaptive immune response according to SAH severity.

• Journal of Convergence for Information Technology
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• v.12 no.4
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• pp.119-125
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• 2022

In the study, we endeavored to investigate the effect of phenylephrine, isoprenaline and prazosin on the tissue-specific vascular contractility and to determine the mechanism involved. There were few reports addressing the question whether thin or thick filament modulation is included in phenylephrine, isoprenaline and prazosin-induced regulation. We hypothesized that isoprenaline and prazosin play a role in tissue-dependent regulation of vascular contractility. Denuded arterial muscles of Sprague-Dawley male rats were suspended in organ baths and isometric tensions were transduced and recorded using isometric transducers and an automatic data acquisition system. Interestingly, sustained continuous contraction of thoracic and abdominal aorta. Furthermore, isoprenaline and prazosin together with phenylephrine inhibited transiently and persistently vasoconstriction of thoracic and abdominal aorta suggesting that additional mechanisms (e.g. decreased receptor density, chemical interaction, postreceptor signaling or distribution of agonists) might be included in the modulation of vascular contractility.

• Journal of Radiation Protection and Research
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• v.47 no.3
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• pp.143-151
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• 2022

Background: After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, biological alterations in the natural biota, including morphological changes of fir trees in forests surrounding the power plant, have been reported. Focusing on the terminal buds involved in the morphological formation of fir trees, this study developed a method for estimating the absorbed radiation dose rate using radionuclide distribution measurements from tree organs. Materials and Methods: A phantom composed of three-dimensional (3D) tree organs was constructed for the three upper whorls of the fir tree. A terminal bud was evaluated using Monte Carlo simulations for the absorbed dose rate of radionuclides in the tree organs of the whorls. Evaluation of the absorbed dose targeted ¹³¹I, ¹³⁴Cs, and ¹³⁷Cs, the main radionuclides subsequent to the FDNPP accident. The dose contribution from each tree organ was calculated separately using dose coefficients (DC), which express the ratio between the average activity concentration of a radionuclide in each tree organ and the dose rate at the terminal bud. Results and Discussion: The dose estimation indicated that the radionuclides in the terminal bud and bud scale contributed to the absorbed dose rate mainly by beta rays, whereas those in 1-year-old trunk/branches and leaves were contributed by gamma rays. However, the dose contribution from radionuclides in the lower trunk/branches and leaves was negligible. Conclusion: The fir tree model provides organ-specific DC values, which are satisfactory for the practical calculation of the absorbed dose rate of radiation from inside the tree. These calculations are based on the measurement of radionuclide concentrations in tree organs on the 1-year-old leader shoots of fir trees. With the addition of direct gamma ray measurements of the absorbed dose rate from the tree environment, the total absorbed dose rate was estimated in the terminal bud of fir trees in contaminated forests.

• Journal of Korean Neurosurgical Society
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• v.65 no.2
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• pp.186-195
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• 2022

Objective : To explore the histological feature of the cervical disc degeneration in patients with degenerative ossification (DO) and its potential mechanisms. Methods : A total of 96 surgical segments, from cervical disc degenerative disease patients with surgical treatment, were divided into ossification group (group O, n=46) and non-ossification group (group NO, n=50) based on preoperative radiological exams. Samples of disc tissues and osteophytes were harvested during the decompression operation. The hematoxylin-eosin staining, Masson trichrome staining and Safranin O-fast green staining were used to compare the histological differences between the two groups. And the distribution and content of transforming growth factor (TGF)-β1, p-Smad2 and p-Smad3 between the two groups were compared by a semi-quantitative immunohistochemistry (IHC) method. Results : For all the disc tissues, the content of disc cells and collagen fibers decreased gradually from the outer annulus fibrosus (OAF) to the central nucleus pulposus (NP). Compared with group NO, the number of disc cells in group O increased significantly. But for proteoglycan in the inner annulus fibrosus (IAF) and NP, the content in group O decreased significantly. IHC analysis showed that TGF-β1, p-Smad2, and p-Smad3 were detected in all tissues. For group O, the content of TGF-β1 in the OAF and NP was significantly higher than that in group NO. For p-Smad2 in IAF and p-Smad3 in OAF, the content in group O were significantly higher than group NO. Conclusion : Histologically, cervical disc degeneration in patients with DO is more severe than that without DO. Local higher content of TGF-β1, p-Smad2, and p-Smad3 are involved in the disc degeneration with DO. Further studies with multi-approach analyses are needed to better understand the role of TGF-β/Smads signaling pathway in the disc degeneration with DO.

• Journal of Korean Society on Water Environment
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• v.40 no.5
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• pp.243-257
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• 2024

Although lakes are an important part of freshwater, research on biological methods for assessing ecological integrity of Korean lakes is insufficient. Therefore, this study aimed to develop Lakes Benthic Macroinvertebrates Multi-Metric Index (LBMMI) to assess the ecological integrity of lakes in Korea to further understand Korean lake's ecosystem. We used biological data from 388 sampling units of national lake monitoring programs from 2022 to 2023 and water quality data from Water Environment Information System (WEIS). As a result, firstly, reference points and disturbed points were selected through Principal Component Analysis (PCA). Secondly, six core metric elements (Pielou's Evenness index (J), Total number of taxa (To.t), Percent of taxa in insecta (% I.t), Percent of individuals in Oligochaeta and chironomidae(tuble) (% OliCht.i), Percent of taxa in Predator (% Pe.t), and Percent of taxa in Clingers (% CL.t) were selected through discriminant analysis and relationship-test. Lastly, LBMMI was calculated for each sampling point by scoring using core metric elements and five grades were assigned for LBMMI scores using a Beta probability distribution model, with the suitability of LBMMI reviewed by comparing it with TSI_KO. LBMMI developed in this study is expected to appropriately assess ecological integrity of Korean lakes and provide a basis for further research on lake environment conservation.

• Journal of the Korean Geotechnical Society
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• v.30 no.1
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• pp.75-91
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• 2014

In this study the analysis is performed for influencing factors on the behavior of rigid piles (short pile) by research papers and case study. The results indicated that the point of virtual fixity should be calculated considering the relative stiffness of soil and pile, and Chang (1937) and P-Y method estimated the similar fixity. The values of ultimate resistances of a vertical pile to a lateral load are different for laboratory and field tests in cohesive soils and its ultimate values in laboratory tests are underestimated and in field tests are under or overestimated. The estimated resistance by Hansen (1961)'s method is similar to the value of field tests. The horizontal resistances to laterally loaded pile in cohesionless soils are overestimated in laboratory tests and generally overestimated in field tests. The ultimate resistances by Zhang (2005)'s method, used to the empirical distribution of the resistance, are similar to the test results. In the paper the calculating method and distribution of the ultimate resistance in cohesive soils are proposed. The estimated value by the proposed method is closer to the test results than any other method of calculating ultimate resistance of the piles embedded into cohesive soils.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.338-347
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• 1997

Apo E polymorphism(e2, e3, e4) was among the first reported genetic polymorphism that explained part of the normal vairation in plasma cholesterol concentrations. Both alleles E2 and E4 are significantly more frequent in patients with mixed forms of hyperlipidemia and contribute on the observed differences in CHD risk among different populations. Effects of apo E polymorphism on the distribution of plasma lipid profiles were studied in 89 normolipidemic healthy females, aged 19 up to 22 years. The relative frequencies of E3/3 was 0.787, E3/2 was 0.101, E3/4 allele was 0.112 and no E2/2, E2/4 and E4/4 were found. Weight, height and %LBM were elevated in E2 than those in E3&E4. No differences in the blood pressure among apo E isomers were found, otherwise the pulsation was higher in E4 than that in the others. There were no differences in plasma total-, total DL-, HDL$_3$-, HDL$_2$ cholesterol, apo B-100 and apo A-I, However, phenotype means rank E3/2>E3/3>E3/4 in average TG levels(p<0.0001) significantly, and rank E3/4>E3/3>E3/2 in LDL cholesterol levels. These results were related to the correlation between atherogenic indiced (AI) such as LDL/HDL, (TC-HDL)/HDL, HDL$_3$/HDL$_2$. The ratio of HDL$_3$& HDL$_2$was significantly increased in E2 & E4 than that in E3(P=0.043). LCAT activity was not different between E2 and E3 but was highly increased in E4 (p<0.0001 among apo E isomers), but CETP was not different. Since the negative correlation between LCAT and CETP in apo E2(r=-0.491) was stronger than that in apo E3, E2 allele impacts the clearance of plasma apo E mediated lipoproteins. In conclusion firstly, E4 mediated alteration through LDL or E receptors results in lower TG or higher $\beta$-lipoprotein levels and E2 shows reciprocal effects of E4, respectively. Second, E4 allele was more atherogenic than E2 allele because the higher levels of AI such as HDL$_3$/HDL$_2$ were criticized.