• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.87-102
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• 2019

Pallancata Ag mine is located at the Ayacucho region 520 km southeast of Lima. The geology of mine area consists of mainly Cenozoic volcanic-intrusive rocks, which are composed of tuff, andesitic lava, andesitic tuff, pyroclastic flow, volcano clasts, rhyolite and quartz monzonite. This mine have about 100 quartz veins in tuff filling regional faults orienting NW, NE and EW directions. The Ag grades in quartz veins are from 40 to 1,000 g/t. Quartz veins vary from 0.1 m to 25 m in thickness and extend to about 3,000 m in strike length. Quartz veins show following textures including zonation, cavity, massive, breccia, crustiform, colloform and comb textures. Wallrock alteration features including silicification, sericitization, pyritization, chloritization and argillitization are obvious. The quartz veins contain calcite, chalcedony, adularia, fluorite, rutile, zircon, apatite, Fe oxide, REE mineral, Cr oxide, Al-Si-O mineral, pyrite, sphalerite, chalcopyrite, galena, electrum, proustite-pyrargyrite, pearceite-polybasite and acanthite. The temperature and sulfur fugacity ($f_{s2}$) of the Ag mineralization estimated from the mineral assemblages and mineral compositions are ranging from 118 to $222^{\circ}C$ and from $10^{-20.8}$ to $10^{-13.2}atm$, respectively. The relatively low temperature and sulfur-oxygen fugacities in the hydrothermal fluids during the Ag mineralization in Pallancata might be due to cooling and/or boiling of Ag-bearing fluids by mixing of meteoric water in the relatively shallow hydrothermal environment. The hydrothermal condition may be corresponding to an intermediate sulfidation epithermal mineralization.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.645-654
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• 2020

We present the K-Ar age dating results of <0.1㎛ fraction of the selected fault rocks from the Yangsan fault in the Yeonghae area. Based on the mineralogical characterization, the <0.1㎛ fractions were mostly composed of 1Md illite polytype, or I-S interstratified mineral, which should be formed by fault activation. Therefore, we determined the timings of fault activation events by analyzing K-Ar age-dating for the <0.1㎛ fractions. Accordingly, the activation timings of Yangsan Fault in the Yeonghae area were determined as 45.5±1.1 Ma, 50.9±1.2 Ma, 58.2±1.3 Ma, 60.8±1.4 Ma, 65.3±1.6 Ma, 66.8±1.5 Ma, 67.1±1.5 Ma, and 75.1±1.7 Ma. These results indicate that at least 5-times of major fault events occurred in the Yangsan fault from late Mesozoic to Cenozoic Era. In the outcrop, age dating results tend to be younger age from the location of the oldest sample(75.1±1.7 Ma) toward to the both sides. From the results, it suggests that the fault activation extends from the location of oldest age saple to both sides. This geochronological research of the multiple fault activation ages for the Yangsan Fault will provide crucial information for establishing the tectonic evolution model in the southeastern part of the Korean Peninsula.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.500-506
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• 2006

Purpose : We evaluated an outbreak of Serratia marcescens infections in 24 neonates in a neonatal intensive care unit(NICU). Methods : From January to August, 2004 a nosocomial outbreak of S. marcescens occurred in our NICU. We describe the clinical characteristics of the outbreak and analyse the risk factors for infections with S. marcescens. After the outbreak stopped, 7 isolates from blood were typed using rapid amplified polymorphic DNA analysis(RAPD). Results : S. marcescens was isolated from 24 neonates, 19 infected and 5 colonized. Seven out of nineteen neonates had bacteremia, 4 had ventilator associated pneumonia, 4 had purulent conjunctivitis, 2 had UTI, 1 had meningitis and 1 had a wound infection. Three neonates died due to S. marcescens infection, 2 of 3 had ventilator associated pneumonia, 1 had meningitis complicated with abscess. The mortality rate of S. marcescens infection was 15.8%. Factors associated with S. marcescens infections were previous antibiotic therapy, indwelling catheter and use of ventilators. The isolated strains were resistant to most antibiotics, but frequently sensitive to imipenem, bactrim and amikacin. RAPD typing results show that at least 3 epidemic strains were related with this outbreak. But one genotype was predominant type in this outbreak. The control measures were instituted and the outbreak stopped within 2 months. Conclusion : S. marcescens can cause rapidly spreading outbreaks associated with fatal infections in neonates. If S. marcescens is isolated from clinical specimens, meticulous infection control measures and epidemiologic investigations should be done at an early stage of the outbreak.

• Journal of the Korean earth science society
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• v.40 no.2
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• pp.163-176
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• 2019

The Potosinian geological basement in central Mexico is comprised of the Upper Paleozoic metamorphic rocks, which crop out on the Sierra de Catorce nucleus located in the northeastern part of the state. The sedimentary sequence that covers unconformably the Paelozoic basement is represented by an Upper Triassic marine sedimentary sequence, correlating to the Zacatecas Formation and the Upper Triassic continental Huizachal Formation red beds, which in turn are covered either by La Joja Formation Jurassic red beds or by Upper Jurassic marine sediments. This sequence is overlain by the conformable Cretaceous calcareous marine sedimentary rocks in all the state of San Luis Potosi. The Cenozoic sequence unconformably covers some of the aforementioned rocks and is represented by undifferentiated volcanic rocks as well as by marine clastic rocks. The existing intrusive igneous rocks are felsic to intermediate composition, and they intrude the metamorphic basement and sedimentary rocks. Conglomerates with evaporitic sediments were deposited during the Pleistocene. The Quaternary sequence includes basalt flows, piedmont deposits, alluvium, and occasionally evaporites and caliche layers. In the state of San Luis Potosi, a great diversity of mineral deposit types is known as both metallic and nonmetallic. The host rocks of these deposits vary from one another including formations that represent from Paleozoic up to Tertiary. The mineralization age corresponds approximately to Tertiary (75%), and is mainly epigenetic. Conclusively, the data on geology and mineralization in San Luis Potosi, Mexico are helpful to predict a hidden ore body and select promising mineralized zone(s) when the domestic company makes inroads in the mining sector of Mexico.

• Journal of the Korea Convergence Society
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• v.9 no.1
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• pp.277-282
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• 2018

This study aims to present a direction for securing continuous growth and confidence, centering on two Internet banking companies that started recently. The banking market has been rewriting the history since the emergence of Internet professional banks. In order to improve the credibility and promote the development of the Internet professional banks, I conducted a questionnaire survey and In Depth Interview. As a result of this survey, the overall reliability is still low, and the factors affecting reliability are: 1.Security problem 2.Discomfort of customer service 3.Errors and unnecessary services. This is a start-up business, so the awareness and reliability can be changed soon. Therefore, it is necessary to continue research on this according to the changing user's perception.

• Journal of Chest Surgery
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• v.30 no.11
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• pp.1121-1124
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• 1997

This is a report of a successful, rapid two-stage arterial switch operation in an infant with dextrotransposition of great arteries with an intact ventricular septum beyond the appropriate time for arterial switch operation.'A 4-month-old female infant was admitted due to severe cyanosis, respiratory insufficiency, and frequent dia rhea secondary to ischemic colitis. Echocardiographic examination presented marked leftward deviation of the interventricular septum, and left and right ventricular pressures as measured by cardiac catheterization were 40/4 mmHg and 85/2 mmHg, respectively. Fifteen days after a preparatory operation (pulmonary artery band with modified right Blalock-Taussig shunt), left ventricular-right ventricular systolic pressure ratio increased to 105/90. Arterial switch operation associated with the division of the right Blalock-Taussig shunt and the removal of pulmonary artery band was performed. A(leer the operation, the infant showed normal cardiac function with no postoperative complication.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.1
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• pp.88-94
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• 2019

Increasing demands for esthetic dental treatment, zirconia, which has high mechanical and esthetic properties, had been applied more and more in clinics. Therefore, assessment of biocompatibility of zirconia is necessary. In this article, a review of in vivo studies of zirconia compatibility was performed. In vivo studies showed zirconia had great biocompatibility both on soft and hard tissue. Studies with various animals and patients reported high biocompatibility of zirconia. In terms of bone synthesis and bone adhesion, zirconia showed similar biocompatible properties to titanium. On the other hand, zirconia could be used as implant. For using as an implant, various methods of Hydroxyapatite (HA) coating had been suggested. Since HA coating on titanium implant showed some problems such as low bonding strength and degeneration of HA, HA-zirconia composite, HA-coated zirconia, and HA-zirconia functionally graded material (FGM) or intermediate layer of alumina had been proposed. These methods showed higher bonding strength and biocompatibility.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.2
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• pp.107-120
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• 2021

The Komdok Pb-Zn deposit, which is the largest Pb-Zn deposit in Korea, is located at the Hyesan-Riwon metallogenic zone in Jiao Liao Ji belt included Paleoproterozoic Macheolryeong group. The geology of this deposit consists of Paleoproterozoic metasedimentary rocks, Jurassic Mantapsan intrusive rocks and Cenozoic basalt. The Komdok deposit which is a SEDEX type deposit occurs as layer ore and vein ore in the Paleoproterozoic metasedimentary rocks. Based on mineral petrography and paragenesis, dolomites from this deposit are classified four types (1. dolomite (D₀) as hostrock, 2. early dolomite (D₁) associated with tremolite, actinolite, diopside, sphalerite and galena from amphibolite facies, 3. late dolomite (D₂) associated with talc, calcite, quartz, sphalerite and galena from amphibolite facies, 4. dolomite (D₃) associated with white mica, chlorite, sphalerite and galena from quartz vein). The structural formulars of dolomites are determined to be Ca_1.00-1.20Mg_0.80-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₀), Ca_1.00-1.02M_0.97-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₁), Ca_0.99-1.03Mg_0.93-0.98Fe_0.01-0.05Mn_0.00-0.01As_0.00-0.01(CO₃)₂(D₂) and Ca_0.95-1.04Mg_0.59-0.68Fe_0.30-0.36Mn_0.00-0.01 (CO₃)₂(D₃), respectively. It means that dolomites from Komdok deposit have higher content of trace elements (FeO, MnO, HfO₂, ZnO, PbO, Sb₂O₅ and As₂O₅) compared to the theoretical composition of dolomite. These trace elements (FeO, MnO, ZnO, Sb₂O₅ and As₂O₅) show increase and decrease trend according to paragenetic sequence, but HfO₂ and PbO elements no show increase and decrease trend according to paragenetic sequence. Dolomites correspond to Ferroan dolomite (D₀, D₁ and D₂), and Ferroan dolomite and ankerite (D₃), respectively. Therefore, 1) dolomite (D₀) as hostrock was formed by subsequent diagenesis after sedimentation of Paleoproterozoic (2012~1700 Ma) silica-bearing dolomite in the marine evaporative environment. 2) Early dolomite (D₁) was formed by hydrothermal metasomatism origined metamorphism (amphibolite facies) associated with intrusion (1890~1680 Ma) of Paleoproterozoic Riwon complex. 3) Late dolomte (D₂) was formed from residual fluid by a decrease of temperature and pressure. and dolomite (D₃) in quartz vein was formed by intrusion (213~181 Ma) of Jurassic Mantapsan intrusive rocks.

• Proceedings of the Botanical Society of Korea Conference
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• 1995.07a
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• pp.109-130
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• 1995

지난 반세기간에 우리나라에 채소 육종은 주요 채소의 주년공급을 가능하게 하였으며, 토지 생산성의 향상, 상품화율의 증대, 품질의 향상 등의 면에서도 괄목할 만한 성과를 거두었고 인공교잡은 물론이고 웅성불임성과 자가불화합성의 활용에 의한 1대잡종 품종의 일반화로 채소 산업의 발전에 크게 기여하였다. 앞으로는 기왕의 업적을 심화시키는 한편, 생산비를 절감하기 위한 생력화, 기계화 재배용 품종 및 내제초제성 품종의 개발 환경보호 및 식품안정성의 확보를 위한 내병층성 품종 개발, 수출시장과 다양화하는 국내의 시장기호에 대응하고 가공 식품의 표준화된 품질관리를 지원할 수 있도록 품질 면에서의 개량과 신작물 또는 신생태형 품종의 개발에도 더욱 노력이 필요하다. 이러한 육종목표를 달성하기 위한 유전자원의 확보는 더욱 어려워질 것이며 유전 양식이 복잡하고, 환경요인의 작용이 상대적으로 크기 때문에 전통적인 육종 방법만으로는 목표달성에 필요한 인적, 물적, 시간적 소요가 훨씬 증가될 전망이다. 유전변이의 창성 및 확대, 유용 대립인자의 도입, 동정 및 선발, 그리고 종자생산을 위한 자가 불화합성 및 웅성불임성과 개화·수정 관련 유전인자의 발현 조절에 분자유전학의 보완적 역할이 기대되며 이렇게 되면 전통육종과 분자유전학간의 잡종강세로 품종 개량의 효율은 크게 높아질 것이다.

• Journal of Chest Surgery
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• v.31 no.3
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• pp.315-318
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• 1998

Primary hemangioperiycytoma is quite rare tumor of the lung and arising from pericyte in external layer of capillaries. Most cases are developed in 4th and 5th decade, are asymptomatic, and have malignant otential. On chest radiography, primary pulmonary hemangiopericytoma shows lobulated, well demarcated, homogeneous soft tissue density. Microscopically, it consisits of numerous vascular spaces of variable size and shape separated by aggregates of tightly packed oval to spindle-shaped cells. Treatment of choice is surgical excision. We report a case of primary pulmonary hemangiopericytoma in a 16-year-old man who had well demarcated homogeneous mass in the superior segment of left lower lobe, but had no symptom. He had undergone left lower lobectomy. He has been followed up for 8 months but has no sign of relapse or metastasis yet.