• Journal of the Korean institute of surface engineering
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• v.56 no.5
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• pp.299-308
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• 2023

In this study, phosphorus (P)-doped nickel cobaltite (P-NiCo₂O₄) and nickel-cobalt layered double hydroxide (P-NiCo-LDH) were synthesized on nickel (Ni) foam as a conductive support using hydrothermal synthesis. The thermal properties, crystal structure, microscopic surface morphology, chemical distribution, electronic state of the constituent elements on the sample surface, and electrical properties of the synthesized P-NiCo₂O₄ and P-NiCo-LDH samples were analyzed using thermogravimetric analysis-differential scanning calorimetry (TGA-DSC), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The P-NiCo₂O₄ electrode exhibited a specific capacitance of 1,129 Fg^-1 at a current density of 1 Ag^-1, while the P-NiCo-LDH electrode displayed a specific capacitance of 1,012 Fg^-1 at a current density of 1 Ag-1. When assessing capacity changes for 3,000 cycles, the P-NiCo₂O₄ electrode exhibited a capacity retention rate of 54%, whereas the P-NiCo-LDH electrode showed a capacity retention rate of 57%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.4
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• pp.362-376
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• 2023

The IUU Fishing Index is composed of 40 indicators. These indicators were grouped by state responsibilities (flag, coastal, port, and general including market) defined in the FAO IPOA-IUU (2001) and then by type into vulnerability, prevalence, and response. A total of 152 coastal nations was surveyed. Korea's total combined IUU Fishing Index was 2.49 in 2019 and 2.91 in 2021, indicating a drop in the ranking to the third worst out of 152 countries followed by China and Russia in 2021. The indicators that increased the IUU fishing risk in 2021 compared to 2019 included seven indicators of prevalence and two indicators of response while those reducing the risk included one prevalence and one response indicator. The IUU Fishing Index revealed that many fisheries observers and monitoring, control and surveillance (MCS) practitioners active in the waters of RFMOs jurisdiction where Korean distant water vessels operate have mentioned concerns about the compliance with RFMO conservation measures or fishing practices. It suggested that strengthening management intervention in the fishing sector is needed. The primary tool for management is the MCS system. Given the logistical difficulty of oversight from land, air and at-sea, there is a need to enhance MCS strategies through logbook data, at-sea observer and electronic monitoring program. It also suggested that MSC fisheries certification and fisheries improvement projects, which are widely used for improving fishing sector performance, could contribute to the eradication of IUU fishing and the promotion of sustainable distant water fisheries.

• Journal of Biomedical Engineering Research
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• v.45 no.1
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• pp.26-36
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• 2024

Functional brain imaging techniques have been used to diagnose psychiatric disorders such as dementia, depression, and autism. Recently, these techniques have also been actively used to study hearing loss. The present study reviewed the application of the functional brain imaging techniques in auditory research, especially those focusing on hearing loss, over the past decade. EEG, fMRI, fNIRS, MEG, and PET have been utilized in auditory research, and the number of research studies using these techniques has been increasing. In particular, fMRI and EEG were the most frequently used technique in auditory research. EEG studies mostly used event-related designs to analyze the direct relationship between stimulus and the related response, and in fMRI studies, resting-state functional connectivity and block designs were utilized to analyze alterations in brain functionality in hearing-related areas. In terms of age, while studies involving children mainly focused on congenital and pre- and post-lingual hearing loss to analyze developmental characteristics with and without hearing loss, those involving adults focused on age-related hearing loss to investigate changes in the characteristics of the brain based on the presence of hearing loss and the use of a hearing device. Overall, ranging from EEG to PET, various functional brain imaging techniques have been used in auditory research, but it is difficult to perform a comprehensive analysis due to the lack of consistency in experimental designs, analysis methods, and participant characteristics. Thus, it is necessary to develop standardized research protocols to obtain high-quality clinical and research evidence.

• Genomics & Informatics
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• v.21 no.4
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• pp.44.1-44.10
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• 2023

Tumor hypoxia, oxygen deprivation state, occurs in most cancers and promotes angiogenesis, enhancing the potential for metastasis. The vascular endothelial growth factor (VEGF) family genes play crucial roles in tumorigenesis by promoting angiogenesis. To investigate the malignant processes triggered by hypoxia-induced angiogenesis across pan-cancers, we comprehensively analyzed the relationships between the expression of VEGF family genes and hypoxic microenvironment based on integrated bioinformatics methods. Our results suggest that the expression of VEGF family genes differs significantly among various cancers, highlighting their heterogeneity effect on human cancers. Across the 33 cancers, VEGFB and VEGFD showed the highest and lowest expression levels, respectively. The survival analysis showed that VEGFA and placental growth factor (PGF) were correlated with poor prognosis in many cancers, including kidney renal cell and liver hepatocellular carcinoma. VEGFC expression was positively correlated with glioma and stomach cancer. VEGFA and PGF showed distinct positive correlations with hypoxia scores in most cancers, indicating a potential correlation with tumor aggressiveness. The expression of miRNAs targeting VEGF family genes, including hsa-miR-130b-5p and hsa-miR-940, was positively correlated with hypoxia. In immune subtypes analysis, VEGFC was highly expressed in C3 (inflammatory) and C6 (transforming growth factor β dominant) across various cancers, indicating its potential role as a tumor promotor. VEGFC expression exhibited positive correlations with immune infiltration scores, suggesting low tumor purity. High expression of VEGFA and VEGFC showed favorable responses to various drugs, including BLU-667, which abrogates RET signaling, an oncogenic driver in liver and thyroid cancers. Our findings suggest potential roles of VEGF family genes in malignant processes related with hypoxia-induced angiogenesis.

• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.273-283
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• 2024

As the adverse environmental impacts due to plastic waste become more severe, there is an increasing demand for developing a sustainable ecosystem using biodegradable polymers. Biodegradable polymers are those that can be biochemically decomposed through the enzymatic activity of microorganisms. Currently, a variety of biodegradable polymers with varying properties is being investigated. In particular, polymer blends with an aim to control the biodegradation rate and mechanical properties are under active research. The biodegradable polymer industry, which has not yet reached economies of scale, does not have a cost advantage compared to petroleum-derived polymers. To overcome this challenge, there is an urgent need to expand its application fields to various high-value industries (separators, electronic materials, and medical fields). This review summarizes the current state-of-the-art biodegradable polymers, polymer blends, and recent research trends in new niche applications.

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.517-530
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• 1994

For the purpose of providing the basic data for health management of workers who are exposed to chromium and for improving the quality of working environment, the authors evaluated blood and urinary level of chromium, the occupational history. AST, ALT, Hb, Hct, nasal specular examinaton on 287 workers who have been dealed chromium compounds in 56 manufacturing Industries of five types, that is, 38 metal plating services(plating),4 manufacture of other fabricated metal products (fabricated metal product), 5 manufacturing of dyestuff(dyestuff), 6 dressing and dyeing of leather(leather), 3 others(manufacture of pottery and ceramic househod wares, motor vehicles, electronic valves and tubes and other electronic components) and also measured the level of chromium in air from February to October 1993. The results were as follows ; 1. The utilized type of chromium compounds was the hexavalent state in plating fabricated metal product dyestuff, leather and the trivalent state in .other, and atmosperic chromium concentration as geometric mean was $0.0138mg/m^3(0.001{\sim}0.068mg/m^3)$ in plating, $0.0115mg/m^3(0.006{\sim}0.015mg/m^3)$ in fabricated matal product, $0.068mg/m^3(0.002{\sim}0.019mg/m^3)$ in dyestuff, $0.0083mg/m^3(0.002{\sim}0.028mg/m^3)$ in leather $0.0039mg/m^3(0.003{\sim}0.005mg/m^3)$ in other by the type of industry and it exceeded TLV-TWA ($0.05mg/m^3$) in five (13.6%) of plating services. 2. The geometric mean of chromium in blood was $1.54{\mu}g/dl(0.10{\sim}3.62{\mu}g/dl)$ in Plantng, $0.94{\mu}g/dl(0.27{\sim}2.82{\mu}g/dl)$ in fabricated metal product, $0.51{\mu}g/dl(0.10{\sim}3.25{\mu}g/dl)$ in dyestuff, $0.87{\mu}g/dl(0.15{\sim}8.00{\mu}g/dl)$ in leather, $0.55{\mu}g/dl(0.20{\sim}2.28{\mu}g/dl)$ in other by the type of industry(p<0.001). 3. The geometric mean of chromium in urine was $14.47{\mu}g/l(6.90{\sim}28.00{\mu}g/l)$ in planting, $4.63{\mu}g/l(0.24{\sim}43.00{\mu}g/l)$ in fabricated metal product, $5.93{\mu}g/l(1.00{\sim}33.00{\mu}g/l)$ in dyestuff, $11.09{\mu}g/l(0.80{\sim}48.00{\mu}g/l)$ in leather, $12.41{\mu}g/l(10.10{\sim}41.00{\mu}g/l)$ in other by the type of industry(p<0.001). 4. As the result of nasal specular examination, twenty four cases (8.4%) of nasal septal perforation among 287 total subjects was observed, and there were 17 (9.7%) cases in plating, 4 csaes (14.3%) in dressing and dyeing of leather. In the comparison of chromium concentration in blood and urine between the perforated group and non-perforated group, the perforated group showed a significantly higher value as $1.883{\pm}3.055{\mu}g/dl\;and\;0.793{\pm}0.815{\mu}g/dl$(P<0.001), $21.31{\pm}34.610{\mu}g/L\;and\;9.304{\pm}11.079{\mu}g/L$ (P<0.001). 5. The mean concentration of chromium in blood, urine and the mean level of AST, ALT, Hb and Hct in exposure group were higher than those of control group(p<0.001).

• Journal of the Mineralogical Society of Korea
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• v.30 no.2
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• pp.59-70
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• 2017

$SiO_2$ is one of the most abundant constituents of the Earth's crust and mantle. Probing its electronic structures at high pressures is essential to understand their elastic and thermodynamic properties in the Earth's interior. The in situ high-pressure x-ray Raman scattering (XRS) experiment has been effective in providing detailed bonding transitions of the low-z materials under extreme compression. However, the relationship between the local atomic structures and XRS features at high pressure has not been fully established. The ab initio calculations have been used to overcome such experimental difficulties. Here we report the partial density of states (PDOS) of O atoms and the O K-edge XRS spectra of ${\alpha}-quartz$, ${\alpha}-cristobalite$, and $CaCl_2$-type $SiO_2$ phases calculated using ab initio calculations based on the full-potential linearized augmented plane wave (FP-LAPW) method. The unoccupied O PDOSs of the $CaCl_2$-type $SiO_2$ calculated with and without applying the core-hole effects present significantly distinctive features. The unoccupied O p states of the ${\alpha}-quartz$, ${\alpha}-cristobalite$ and $CaCl_2$-type $SiO_2$ calculated with considering the core-hole effect present similar features to their calculated O K-edge XRS spectra. This confirms that characteristic features in the O K-edge XRS stem from the electronic transition from 1s to unoccupied 2p states. The current results indicate that the core-hole effects should be taken in to consideration to calculate the precise O K-edge XRS features of the $SiO_2$ polymorphs at high pressure. Furthermore, we also calculated O K-edge XRS spectrum for $CaCl_2$-type $SiO_2$ at ~63 GPa. As the experimental spectra for these high pressure phases are not currently available, the current results for the $CaCl_2$-type $SiO_2$ provide useful prospect to predict in situ high-pressure XRS spectra.

• Sleep Medicine and Psychophysiology
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• v.26 no.2
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• pp.104-110
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• 2019

Objectives: Insomnia patients who visited the psychiatric outpatient of a university department, were divided into those patients with insomnia alone and those with depression or anxiety disorder, along with insomnia. The study analyzed their demographic characteristics and the differences in State-Trait Anxiety Inventory (STAI) results among the patient groups. Methods: Patients who visited the psychiatric department in Konkuk University hospital from 1 January 2006 to 31 December 2018. If they were diagnosed with insomnia disorder based on DSM IV-TR and had undergone STAI, their electronic records were retrospectively analyzed. Based on the records, the patients were classified into those with insomnia disorder only, those with insomnia and anxiety disorder, and those with insomnia and depressive disorder. This study analyzed the demographic characteristics and STAI results of each group, and compared the differences among those groups. Results: During the period, 99 of 329 insomnia disorder patients who had performed STAI were diagnosed with depressive concurrent disorder and 61 with concurrent anxiety disorder. There was no difference in demographic characteristics of age and sex ratio among the three patient groups, and all had greater than 70% proportions of patients aged from 50s to 70s (71.8%, 77.1%, and 73.8% respectively). The average scores of STAI-I were 51.85 ± 10.15 for the patients with anxiety disorders and 54.18 ± 10.32 for those with depressive disorders, both of which were higher than the score of the patients with insomnia alone (44.55 ± 8.89). However, the score difference was not statically significant between the anxiety and depression groups. Similarly, in the STAI-II comparison, the averages of patients with anxiety or depressive disorders along with insomnia were 49.98 ± 8.31 and 53.19 ± 10.13 respectively, which were higher than that of the insomnia only group (42.71 ± 8.84), but there was no significant difference between the anxiety and depressive disorder groups. Conclusion: Although there were no differences in demographic data between the patients with insomnia only and those with accompanying depressive or anxiety disorder, the STAI-I and II scores were lower in the insomnia only group. In the future, it is necessary to consider other demographic characteristics including comorbidities and to conduct similar analyses with a larger sample.

• Journal of the Korean Magnetics Society
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• v.18 no.6
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• pp.211-216
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• 2008

The effects of Si impurity on electronic structures and magnetism of bcc Fe are investigated by using a first-principles method by considering spin-orbit coupling. In order to describe the Si impurity, a 27 atomic bcc Fe supercell has been considered. The Kohn-Sham equation was solved in terms of the all-electron full-potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA). The effects of spin-orbit coupling were calculated self-consistently by considering spin-diagonal terms based on second variation method. For the ferromagnetic (FM) state without considering SOC, the spin magnetic moment of the Si impurity was calculated to be $-0.143{\mu}B$, while the magnetic moments of Fe atoms were calculated to be $2.214{\mu}B$, $2.327{\mu}B$, and $2.354{\mu}B$ in away from the Si atom, respectively. However, the FM state with considering SOC, the spin magnetic moment of the Si impurity was calculated to be $-0.144{\mu}B$, which is not affected significantly by SOC, but the spin magnetic moments of Fe atoms were calculated $2.189{\mu}B$, $2.310{\mu}B$, and $2.325{\mu}B$, respectively, which are much reduced value compared to those of the FM state without SOC. Comparing the total charge density and spin density, those features are thought to be originated by the screening distortions of the Fe $t_{2g}$ orbital, which can be obtained by considering SOC.

• Journal of Arbitration Studies
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• v.12 no.1
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• pp.271-321
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• 2002

Every year, many million of business transactions take place. Ocassionally, disagreements develop over these business transactions. Many of these disputes are resolved by mediation, arbitration and out-of-court settlement options. The American Arbitration Association(AAA) helps resolve a wide range of disputes through mediation, arbitration, elections and other out-of-court settlement procedures. The AAA offers a broad range of dispute resolution services to business executives, attorneys, individuals, trade associations, unions, management, consumers, families, communities, and all level of governments. The 198,491 cases composed of the 194,303 arbitration cases and the 4,188 mediation cases, were filed with the AAA in 2000. These case filings represent a full range of matters, including commercial finance, construction, labor and employment, environmental, health care, insurance, real state, securities, and technology disputes. The Korean Commercial Arbitration Board (KCAB) does more than render arbitration services. It helps facilitate settlements and guarantee implementation thereof between trading partners at home and abroad involving disputes related to such areas as the sale of commodities, construction, joint venture agreements, technical assistance, agency agreements, and maritime transport. The 643 cases composed of the the 197 arbitration cases and the 446 mediation cases, were filed with the KCAB in 2001. There are some differences between the AAA and the KCAB regarding the number and the area of mediation and arbitration case filings, the breath of service offerings, the scope of alternative dispute resolution, and the education and training. In order to apply to the proceedings of the commercial mediation and arbitration, the AAA has the Commercial Mediation Rules, the Commercial Arbitration Rules, the Expedited Procedures, the Optional Procedures for Large, Complex Commerical Dispute, and the Optional Rules for Emergency Measures of Protection as amended and effective on September 1, 2000. In order to apply to the proceedings of commercial arbitration, the KCAB has the Arbitration Rules as amended by the Supreme Court on April 27, 2000, which have been changed to incorporate the revisions of the Arbitration Act that went into effect on December 31, 1999. There are some differences between the AAA's commercial Arbitration Rules and the KCAB's Arbitration Rules regarding the clauses of jurisdiction and administrative conference, number of arbitrators, communication with arbitrator, vacancies, preliminary hearing, exchange of information, oaths, evidence by affidavit and posthearing filing of documents or others, interim measures, serving of notice, form of award, scope of award, delivery of award to parties, modification of award, release of liability, administrative fees, neutral arbitrator's compensation, and expedited procedures. In conclusion, for the vitalization of KCAB and its ADR system, the following measures should be taken : the effective case management, the development of on0-line ADR, the establishment of ADR system of electronic commerce disputes, and the variety of dispute resolution rules in each expert field.