• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.8
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• pp.678-681
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• 2011

We have investigated the effect of organic thin film on the driving voltage of OLED (organic light emitting diode) by inserting a 5 nm thick 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or triphenylphosphineoxide ($Ph_3PO$) between tris-(8-hydroxyquinoline)aluminum ($Alq_3$) electron transport layer and 4,4'-bis(2,2'-diphyenylvinyl)-1,1'-biphenyl (DPVBi) emission layer. The device with 5 nm thick $Ph_3PO$ layer exhibited higher maximum current efficiency and lower driving voltage than the device with BCP layer, resulting from better electron injection from $Alq_3$ to DPVBi in the device with $Ph_3PO$ layer.

• Bulletin of the Korean Mathematical Society
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• v.49 no.1
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• pp.175-195
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• 2012

Representing planar Pythagorean hodograph (PH) curves by the complex roots of their hodographs, we standardize Farouki's double cubic method to become the undetermined junction point (UJP) method, and then prove the generic existence of solutions for general $C^1$ Hermite interpolation problems. We also extend the UJP method to solve $C^2$ Hermite interpolation problems with multiple PH cubics, and also prove the generic existence of solutions which consist of triple PH cubics with $C^1$ junction points. Further generalizing the UJP method, we go on to solve $C^2$ Hermite interpolation problems using two PH quintics with a $C^1$ junction point, and we also show the possibility of applying the modi e UJP method to $G^2[C^1]$ Hermite interpolation.

• BMB Reports
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• v.54 no.2
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• pp.112-117
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• 2021

Phospholipase D2 (PLD2) has been implicated in the tyrosine kinase-mediated signaling pathways, but the regulation events are yet to be identified. Herein, we demonstrate that pleckstrin homology (PH) domain of PLD2 (PLD2-PH) exerts an antitumorigenic effect via the suppression of PLD2 and focal adhesion kinase (FAK). The kinase domain of FAK interacts with PLD2-PH and induces tyrosine phosphorylation and activation of PLD2. Furthermore, PLD2 increased tyrosine phosphorylation of FAK. However, ectopic expression of the PLD2-PH competes for binding to FAK and reduces the interaction between PLD2 and FAK, thereby suppressing FAK-induced PLD activation and tyrosine phosphorylation of FAK. The PLD2-PH suppressed the migration and invasion of glioblastoma cells, as well as tumor formation in a xenograft mouse model. This study uncovers a novel role of PLD2-PH as a negative regulator of PLD2 and FAK.

• Bulletin of the Korean Chemical Society
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• v.4 no.4
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• pp.180-183
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• 1983

The reaction of $IrClH_2(CO)(Ph_3P)_2$ ($Ph_3P$=triphenylphosphine) with acrylonitrile (AN) produces a stoichiometric amount of propionitrile (PN) at $100^{\circ}C$ under nitrogen, which suggests that the catalytic hydrogenation of AN to PN with $IrCl(CO)(Ph_3P)_2$ proceeds through the hydride route where the formation of the dihydrido complex, $IrClH_2(CO)(Ph_3P)_2$ is the initial step. The rate of the hydrogenation of AN to PN with $IrCl(CO)(Ph_3P)_2$ is decreased by the presence of excess $Cl^-$ in the reaction system, which suggests that $Cl^-$ is the dissociating ligand in the catalytic cycle. It has been also found that the rate of the hydrogenation increases with inercase both in hydrogen pressure and in concentration of free $Ph_3P$, and with decrease in AN concentration in the reaction system.

• Elastomers and Composites
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• v.55 no.4
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• pp.281-288
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• 2020

A calibration curve is needed to determine the SBR and BR blend ratio of SBR/BR blend rubber compounds using pyrolysis-gas chromatography/mass chromatography (Py-GC/MS) or Py-GC. In general, a calibration curve is obtained using reference SBR/BR vulcanizates with various blend ratios. In this study, the calibration curves were obtained using reference samples made of rubber solutions and were compared to those plotted using the reference SBR/BR vulcanizates. Calibration curves using variations of 1,3-butadiene/styrene, 4-vinylcyclohexene (VCH)/styrene, 2-phenylpropene (PhP)/butadiene, PhP/VCH, 4-phenylcyclohexene (PhCH)/butadiene, and PhCH/VCH ratios with the BR content were examined for the suitability. We found that the calibration curves obtained using the mixed rubber solution references (1,3-butadiene/styrene and PhP/butadiene) could replace those constructed using the reference SBR/BR vulcanizates. The calibration curves of 1,3-butadiene/styrene and PhP/butadiene obtained using the raw references can be used for the determination of the SBR/BR blend ratios by applying some correction factors.

• Korea journal of population studies
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• v.29 no.1
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• pp.157-183
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• 2006

This study examines the factors that influence the chance of getting a full-time tenure track? position in universities in biochemistry. Its main findings are: first, as age at the time of getting a Ph.D. degree increases and the more recent a birth-cohort a female Ph.D. belonged to, the more likely she was likely to get a job; second, the number of citations of publications in science-citation indexed journals during a Ph.D. program period and the number of publications in science-citation indexed journals in post Ph.D. period increased her chance of getting a job; third, a post doctoral program and the duration of Ph.D. training did not affect a chance of getting a job; finally, a Ph.D. from a foreign university and a prestige ranking of a Ph.D. program did not influence a chance of getting a job.

• The Korea Journal of Herbology
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• v.20 no.3
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• pp.93-100
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• 2005

Objective : Patriniae Herba (PH) has long been used as a remedy for treating infectious diseases in Korea. In the present experiments, the author examined the effects of PH on the cholecystokinin-octapeptide (CCK)-induced acute pancreatitis (AP) in rats. Methods : Male Wistar rat weighing 200 to 250 g were divided into three groups. Normal untreated group, in treatment with PH group; PH (1g/kg) was administered orally, followed by $75\;{\mu}g/kg$ CCK subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 days. In treatment with saline group, the protocol was the same as in treatment group with PH. The author determined the pancreatic weight/body weight ratio, the levels of pancreatic HSP60, HSP72 and the secretion of pro-inflammatory cytokines. Methods : Repeated CCK treatment resulted in the typical laboratory and morphological changes of experimentally induced pancreatitis. PH was significantly decreased the pancreatic weight/body weight ratio in CCK-induced AP. Futhermore, the author demonstrated that PH increased HSP60 and HSP72 compared with CCK-induced AP. Additionally, the secretion of $TNF-{\alpha},\;IL-1{\beta}$ and IL-6 the levels of amylase and lipase were lower than that saline. Conclusions : These results suggest that PH may has a inhibitory effect against CCK-induced AP.

• Childhood Kidney Diseases
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• v.23 no.2
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• pp.59-66
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• 2019

Background: Primary hyperoxaluria (PH), a rare inborn error of glyoxylate meta bolism causing overproduction of oxalate, is classified into three genetic subgroups: type 1-3 (PH1-PH3) caused by AGXT, GRHPR, and HOGA1 gene mutations, respectively. We performed a retrospective case series study of Korean pediatric patients with PH. Methods: In total, 11 unrelated pediatric patients were recruited and their phenotypes and genotypes were analyzed by a retrospective review of their medical records. Results: Mutational analyses revealed biallelic AGXT mutations (PH1) in nine patients and a single heterozygous GRHPR and HOGA1 mutation in one patient each. The c.33dupC was the most common AGXT mutation with an allelic frequency of 44%. The median age of onset was 3 months (range, 2 months-3 years), and eight patients with PH1 presented with end stage renal disease (ESRD). Patients with two truncating mutations showed an earlier age of onset and more frequent retinal involvement than patients with one truncating mutation. Among eight PH1 patients presenting with ESRD, five patients were treated with intensive dialysis followed by liver transplantation (n=5) with/without subsequent kidney transplantation (n=3). Conclusion: Most patients presented with severe infantile forms of PH. Patients with two truncating mutations displayed more severe phenotypes than those of patients with one truncating mutation. Sequential liver and kidney transplantation was adopted for PH1 patients presenting with ESRD. A larger nation-wide multicenter study is needed to confirm the genotype-phenotype correlations and outcomes of organ transplantation.

• Earthquakes and Structures
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• v.26 no.3
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• pp.175-189
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• 2024

Aiming at studying the plastic hinge (PH) evolution regularities and failure mode of rocking wall moment frame (RWMF) structure in earthquakes, the whole-working history analysis of seismic performance state of RWMF structure based on co-operation performance and PH evolution was carried out. Building upon the theoretical analysis of the elastic internal forces and deformations of RWMF structures, nonlinear finite element analysis (FEA) methods were employed to perform both Pushover analysis and seismic response time history analysis under different seismic coefficients (δ). The relationships among PH occurrence ratios (R_ph), inter-story drifts and δ were established. Based on the plotted curve of the seismic performance states, evaluation limits for the R_ph and inter-story drifts were provided for different performance states of RWMF structures. The results indicate that the R_ph of RWMF structures exhibits a nonlinear evolution trend of "fast at first, then slow" with the increasing of δ. The general pattern is characterized by the initial development of beam hinges in the middle stories, followed by the development towards the top and bottom stories until the beam hinges are fully formed. Subsequently, the development of column hinges shifts from the bottom and top stories towards the middle stories of the structure, ultimately leading to the loss of seismic lateral capacity with a failure mode of partial beam yield, demonstrating a global yielding pattern. Moreover, the limits for the R_ph and inter-story drifts effectively evaluate the five different performance states of RWMF structures.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1292-1296
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• 2007

To investigate the gel properties of surimi-like materials (SLM) made from pig heart (PH), psoas major muscle (PM) and semimembranosus muscle (SM) of pigs, the three muscles were diced, chopped and washed with 25 mM sodium phosphate buffer (pH 7.0) to extract myofibrillar protein. SLM from SM had significantly (p<0.05) higher moisture content and lower crude protein content compared with PH and PM samples. The cooked SLM from PH was darker than that from PM and SM. Gel from PH had significantly (p<0.05) lower L* and hue values, and higher b* and chroma values compared to gels from PM and SM. The cooked SLM from PH had poor water-holding capacity (WHC) resulting in higher cooking loss. SDS-PAGE showed that the bands of myosin and tropomyosin/troponin had reduced staining intensity in the PH sample, and some unidentified bands that were not in PM and SM samples were observed in PH samples.