• Title/Summary/Keyword: Center Bearing

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Radioimmunotherapy of Nude Mice Bearing Human Colon Carcinoma with I-131 Labeled Anti-carcinoembryonic Antigen Monoclonal Antibody (누드마우스에 이식된 인체대장암에서 I-131표지 항태아성암항원 단일클론항체를 이용한 방사면역치료법 : 치료성적에 관계되는 인자분석)

  • Kim, Byung-Tae;Lee, Kyung-Han;Kim, Sang-Eun;Choi, Yong;Chi, Dae-Yoon;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Chung, Hong-Keun
    • The Korean Journal of Nuclear Medicine
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    • v.29 no.3
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    • pp.332-342
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    • 1995
  • This study was designed to evaluate the effects of various factors on the therapeutic effect of the I-131 labeled anti-carcinoembryonic antigen monoclonal antibody(anti-CEA antibody). Tetrazolium-based colorimetric assay (MTT) was used to compare in vitro cytotoxicity of 3 Korean colon cancer cell lines (SNU-C2A, SNU-C4, SNU-C5) for selection of proper 2 cell lines in this study. The changes of the size of tumor which was xenografted to nude mice (balb/c nu/nu) were compared in 4 groups (group treated I-131 labeled anti-CEA antibody, group treated with non-radiolabeled anti-CEA antibody, group treated with I-131 labeled anti-human chorionic gonadotropin monoclonal antibody (anti-hCG antibody) as nonspecific antibody, and group injected with normal saline as a control). Immunohistochemical staining and in vivo autoradiography were performed after excision of the xenografted tumor. The results were as below mentioned. The in vitro cytotoxic effect of I-131 labeled anti-CEA antibody is most prominent in SNU-C5 cell line between 3 cancer cell lines. The changes of xenografted tumor size in both SNU-C4 and SNU-5S cell tumors at the thirteenth day after injection of the antibodies were smallest in the group treated with I-131 labeled anti-CEA antibody (SNU-C4/SNU-C5; 324/342%) comparing with other groups, group treated with anti-CEA antibody (622/660%), group treated with I-131 anti-hCG antibody (538/546%), and control group(1030/724%)(P<0.02 in SNU-C4 and P<0.1 in SNU-C5 at the 13th day after injection of antibodies). On the thirteenth day after injection of the antibodies nude mice were sacreficed to count the radiouptake of tumor and to check the changes of tumor size. Correlations between radiouptake and change of tumor size were calculated in each groups and significant negative correlation was only obtained in the group treated with I-131 anti-CEA antibody (p<0.05). There were no correlations between antigenic expression of carcinoembryonic antigen and distribution of anti-CEA antibody in both SNU-C4 and SNU-C5 cell tumors on immunoperoxidase staining. On in vivo autoradiography the distributions of anti-CEA antibody were heterogeneous and the intensities of binding were various in SNU-C4 and SNU-C5 cell tumors. It is concluded that I-131 labeled tumor-specific monoclonal antibody, anti-CEA antibody is effective in suppressing the xenografted tumor growth and the effect is influenced by sensitivity of tumor cell itself to the radiolabeled antibody and other local factors instead of specificity of antibody.

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Clinical Results of Anterolateral Thigh Perforator Flap for Soft Tissue Reconstruction of the Foot and Ankle (족부 및 족관절부 연부조직 재건을 위한 전외측 대퇴 천공지 피판술의 임상결과)

  • Han, Soo-Hong;Hong, In Tae;Lee, Yohan;Jo, Yong-Gil;Kwon, Young Woo
    • Journal of the Korean Orthopaedic Association
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    • v.52 no.1
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    • pp.40-48
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    • 2017
  • Purpose: Soft tissue reconstruction of a defect around the foot and ankle is a particularly challenging procedure due to the anatomical and functional characteristics of this area. Hence, only a limited number of treatment options are available. Moreover, if patients wish to avoid additional scars on the ipsilateral lower leg for cosmetic reasons, even fewer options are available for treatment. The authors used an anterolateral thigh perforator flap for soft tissue defects in this area, when other surgical options were inadequate. The aim of this study was to report the clinical results and the efficacy of this procedure. Materials and Methods: Sixteen cases of soft tissue defects around the foot and ankle were included. Participants included 12 male and 4 female subjects, and the mean age was 34 years. The most common cause of defect was acute trauma, and the average follow-up period was 33 months. Flap survival time, surgical complications, and ambulation status at the final follow-up stage were evaluated. Results: All 16 flaps successfully survived, except for one case with partial flap necrosis that was thought to be due to weight bearing earlier than scheduled. All patients were able to walk independently without any aid at the final follow-up stage. No patients showed other significant surgical complications. Conclusion: The anterolateral thigh perforator flap is a good alternative for soft tissue defects of the foot and ankle, when other options are not applicable. This study also demonstrated that surgery using an anterolateral thigh perforator flap is safe and highly reliable.

Small Animal PET Imaging with [$^{124}I$]FIAU for Herpes Simplex Virus Type 1 Thymidine Kinase Gene Expression in a Hepatoma Model (간암 동물 모델에서 2'-fluoro-2'-deoxy-1-${\beta}$-D-arabinofuranosyl-5-[$^{124}I$iodo-uracil ($[^{124}I]FIAU$) 소동물 PET 영상 연구)

  • Chae, Min-Jeong;Lee, Tae-Sup;Kim, June-Youp;Woo, Gwang-Sun;Jumg, Wee-Sup;Chun, Kwon-Soo;Kim, Jae-Hong;Lee, Ji-Sup;Ryu, Jin-Sook;Cheon, Gi-Jeong;Choi, Chang-Woon;Lim, Sang-Moo
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.3
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    • pp.235-245
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    • 2008
  • Purpose: The HSV1-tk gene has been extensively studied as a type of reporter gene. In hepatocellular carcinoma (HCC), only a small proportion of patients are eligible for surgical resection and there is limitation in palliative options. Therefore, there is a need for the development of new treatment modalities and gene therapy is a leading candidate. In the present study, we investigated the usefulness of substrate, 2'-fluoro-2'-deoxy-1-${\beta}$-D-arabino-furanosyi-5-[$^{124/125}I$]iodo- uracil ([$I^{124/125}I$]FIAU) as a non-invasive imaging agent for HSV1-tk gene therapy in hepatoma model using small animal PET. Material and Methods: With the Morris hepatoma MCA cell line and MCA-tk cell line which was transduced with the HSV1-tk gene, in vitro uptake and correlation study between [$^{125}I$]FIAU uptake according to increasing numeric count of percentage of MCA-tk cell were performed. The biodistribution data and small animal PET images with [$^{124}I$]FIAU were obtained with Balb/c-nude mice bearing both MCA and MCA-tk tumors. Results:, Specific accumulation of [[$^{125}I$]FIAU was observed in MCA-tk cells but uptake was low in MCA cells. Uptake in MCA-tk cells was 15 times higher than that of MCA cells at 480 min. [$^{125}I$]FIAU uptake was linearly correlated (R2 =0.964, p =0.01) with increasing percentage of MCA-tk numeric cell count. Biodistribution results showed that [$^{125}I$]FIAU was mainly excreted via the renal system in the early phase. Ratios of MCA-tk tumor to blood acting were 10, 41, and 641 at 1 h, 4 h, and 24 h post-injection, respectively. The maximum ratio of MCA-tk to MCA tumor was 192.7 at 24 h. Ratios of MCA-tk tumor to liver were 13.8, 66.8, and 588.3 at 1 h, 4 h, and 24 h, respectively. On small animal PET, [$^{124}I$]FIAU accumulated in substantial higher levels in MCA-tk tumor and liver than MCA tumor. Conclusion: FIAU shows selective accumulation to HSV1-tk expressing hepatoma cell tumors with minimal uptake in normal liver. Therefore, radiolabelled FIAU is expected to be a useful substrate for non-invasive imaging of HSV1-tk gene therapy and therapeutic response monitoring of HCC.

Occurrence and Chemical Composition of W-Bearing Rutile from the Unsan Au Deposit (운산 금 광상에서 산출되는 함 텅스텐 금홍석의 산상과 화학조성)

  • Yoo, Bong Chul
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.2
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    • pp.115-127
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    • 2020
  • The Unsang gold deposit has been one of the three largest deposits (Daeyudong and Kwangyang) in Korea. The deposit consists of Au-bearing quartz veins filling fractures along fault zones in Precambrian metasedimentary rock and Jurassic Porphyritic granite, which suggests that it might be an orogenic-type. Based on its mineral assemblages and quartz textures, quartz veins are classified into 1)galena-quartz, 2)pyrrhotite-quartz, 3)pyrite-quartz, 4)pegmatic quartz, 5)muscovite-quartz, and 6)simple quartz vein types. The pyrite-quartz vein type we studied shows the following alteration features: sericitization, chloritization, and silicification. The quartz vein contains minerals including white quartz, white mica, chlorite, pyrite, rutile, calcite, monazite, zircon, and apatite. Rutile with euhedral or medium aggregate occur at mafic part from laminated quartz vein. Two types of rutile are distinguishable in BSE image, light rutile is texturally later than dark rutile. Chemical composition of rutile has 89.69~98.71 wt.% (TiO2), 0.25~7.04 wt.% (WO3), 0.30~2.56 wt.% (FeO), 0.00~1.71 wt.% (Nb2O5), 0.17~0.35 wt.% (HfO2), 0.00~0.30 wt.% (V2O3), 0.00~0.35 wt.% (Cr2O3) and 0.04~0.25 wt.% (Al2O3), and light rutile are higher WO3, Nb2O5 and FeO compared to the dark rutile. It indicates that dark rutile and light rutile were formed at different stage. The substitution mechanisms of dark rutile and light rutile are suggested as followed : dark rutile [(V3+, Cr3+) + (Nb5+, Sb5+) ↔ 2Ti4+, 4Cr3+ (or 2W6+) ↔ 3Ti4+ (W6+ ↔ 2Cr3+), V4+ ↔ Ti4+], light rutile [2Fe3+ + W6+ ↔ 3Ti4+, 3Fe2+ + W6+ ↔ Ti4+ + (V3+, Al3+, Cr3+) +Nb5+], respectively. While the dark rutile was formed by cations including V3+, V4+, Cr3+, Nb5+, Sb5+ and W6+ by regional metamorphism of hostrock, the postdating light rutile was formed by redistribution of cations from predating dark rutile and addition of Fe2+ and W6+ from Au-bearing hydrothermal fluid during ductile shear.

Occurrence and Chemical Composition of Ti-bearing Minerals from Drilling Core (No.04-1) at Gubong Au-Ag Deposit Area, Republic of Korea (구봉 금-은 광상일대 시추코아(04-1)에서 산출되는 함 티타늄 광물들의 산상과 화학조성)

  • Bong Chul Yoo
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.3
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    • pp.185-197
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    • 2023
  • The Gubong Au-Ag deposit consists of eight lens-shaped quartz veins. These veins have filled fractures along fault zones within Precambrian metasedimentary rock. This has been one of the largest deposits in Korea, and is geologically a mix of orogenic-type and intrusion-related types. Korea Mining Promotion Corporation drilled into a quartz vein (referred to as the No. 6 vein) with a width of 0.9 m and a grade of 27.9 g/t Au at a depth of -728 ML by drilling (No. 90-12) in the southern site of the deposit, To further investigate the potential redevelopment of the No. 6 vein, another drilling (No. 04-1) was carried out in 2004. In 2004, samples (wallrock, wallrock alteration and quartz vein) were collected from the No. 04-1 drilling core site to study the occurrence and chemical composition of Ti-bearing minerals (ilmenite, rutile). Rutile from mineralized zone at a depth of -275 ML occur minerals including K-feldspar, biotite, quartz, calcite, chlorite, pyrite in wallrock alteration zone. Ilmenite and rutile from ore vein (No. 6 vein) at a depth of -779 ML occur minerals including white mica, chlorite, apatite, zircon, quartz, calcite, pyrrhotite, pyrite in wallrock alteration zone and quartz vein. Based on mineral assemblage, rutile was formed by hydrothermal alteration (chloritization) of Ti-rich biotite in the wallrock. Chemical composition of ilmenite has maximum values of 0.09 wt.% (HfO2), 0.39 wt.% (V2O3) and 0.54 wt.% (BaO). Comparing the chemical composition of rutile at a depth -275 ML and -779 ML, Rutile at a depth of -779 ML is higher contents (WO3, FeO and BaO) than rutile at a depth of -275 ML. The substitutions of rutile at a depth of -275 ML and -779 ML are as followed : rutile at a depth of -275 ML Ba2+ + Al3+ + Hf4+ + (Nb5+, Ta5+) ↔ 3Ti4+ + Fe2+, 2V4+ + (W5+, Ta5+, Nb5+) ↔ 2Ti4+ + Al3+ + (Fe2+, Ba2+), Al3+ + V4++ (Nb5+, Ta5+) ↔ 2Ti4+ + 2Fe2+, rutile at a depth of -779 ML 2 (Fe2+, Ba2+) + Al3+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + (V4+, Hf4+), Fe2+ + Al3+ + Hf 4+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + V4+ + Ba2+, respectively. Based on these data and chemical composition of rutiles from orogenic-type deposits, rutiles from Gubong deposit was formed in a relatively oxidizing environment than the rutile from orogenictype deposits (Unsan deposit, Kori Kollo deposit, Big Bell deposit, Meguma gold-bearing quartz vein).

Study on the Safety of Firefly Luciferase in Human as a Transient Reporter Gene of Oncolytic Virotherapy (항암 바이러스 치료제의 보고유전자로써 반딧불이 루시퍼레이즈의 인체 내 안전성에 대한 연구)

  • Hong, Young Mi;Yoon, Woong Hee;Lee, You Ra;Kim, Soo Ji;Ngabire, Daniel;Narayanasamy, Badrinath;Ornella, Mefotse Saha Cyrelle;Kim, Myunghee;Cho, Euna;Lee, Bora;Hwang, Tae-Ho
    • Journal of Life Science
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    • v.31 no.11
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    • pp.1028-1036
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    • 2021
  • Firefly luciferase (FLuc) can function as an efficient marker in the gene and viral therapies. Nonetheless, its clinical translation has been unaccomplished with the concerns on its exogenous nature and the similarity with human fatty acyl-CoA synthetase. In this study, we aimed to show safety of FLuc by conducting a set of preclinical experiments and a human use. Initially, FLuc permeability across the plasma membrane was investigated by delivering the FLuc-carrying viral vector, OTS-412, or the FLuc recombinant protein. After in vitro infection of OTS-412 into different cancer cell lines, FLuc activity was detected only in the cell lysates, but not in culture media. In addition, recombinant FLuc protein further showed the impermeability against the plasma membrane. Similar result was also observed in the in vivo experiment. After being injected into the VX2 tumor-bearing rabbit, the FLuc exclusively resided within the tumor tissue without being detected in the blood plasma or other organs. Human cancer cell lines originated from various organs were lysed and treated to the FLuc, and none of the human substrates was reactive against the FLuc. As a final step, FLuc recombinant protein was intravenously injected into a human. The luciferase was degraded with the half-life of 20 to 30 minutes in blood, and was untraceable from 1.5 hr after the injection. In addition, the blood plasma was nonresponsive against the fatty acids. Hematological analysis was also comparable between the pre- and post-injection. Altogether, our study collectively demonstrates the safety of the firefly luciferase.

Distribution, Preservation Characteristics of Land and River Natural Aggregates in Nonsan City, Korea (논산시 하천 및 육상 골재 자원의 부존 현황과 특성)

  • Hyun Ho Yoon;Sei Sun Hong;Min Han;Jin-Young Lee
    • Economic and Environmental Geology
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    • v.57 no.2
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    • pp.143-159
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    • 2024
  • Natural aggregate is an essential resource for human activities, closely related to construction. The aggregate demand has been increasing annually, and due to the nature of the resource, it is difficult to procure from distant locations. This study identifies the distribution and characteristics of aggregate-bearing areas as part of a municipal-level aggregate resource survey conducted in Nonsan City, Korea, in 2023. Nonsan City is located approximately 35 km straight distance from the Geum River estuary and lies at the passageway of the main stream of the Geum River. The topography of Nonsan City features eastern mountainous areas and western plains, creating an east-high-west-low geomorphic setting, with 33 streams distributed across the city, including tributaries of the Geum River like Nonsan Stream, Noseong Stream, and Ganggyeong Stream. All streams originate from the highlands in the north and east, converge with Nonsan Stream, and then join the west bank of the main stream of the Geum River at the western boundary of Nonsan City. Drilling core results show shallow depths in the highlands to the north and east, deepening towards the west, reaching a maximum depth of 25 m near the main stream of the Geum River. The total reserve of land aggregates is calculated to be 246,789,000 m3, with a developable amount of 172,750,000 m3. The total reserve of river aggregates is 5,236,000 m3, with a developable amount of 3,765,000 m3. The distribution of aggregates varies according to the geomorphic, geologic, and development pattern of the river system. Reserves are scarce in mountainous areas but are abundant in regions with rivers and wide alluvial plains, although reserves appear at depths greater than 4m. The distribution of aggregate resources in Nonsan City is influenced by stream activities and sea level changes, with the tidal range of the Yellow Sea acting as an unfavorable condition for the preservation of aggregate resources.

Evaluation of HalcyonTM Fast kV CBCT effectiveness in radiation therapy in cervical cancer patients of childbearing age who performed ovarian transposition (난소전위술을 시행한 가임기 여성의 자궁경부암 방사선치료 시 난소선량 감소를 위한 HalcyonTM Fast kV CBCT의 유용성 평가 : Phantom study)

  • Lee Sung Jae;Shin Chung Hun;Choi So Young;Lee Dong Hyeong;Yoo Soon Mi;Song Heung Gwon;Yoon In Ha
    • The Journal of Korean Society for Radiation Therapy
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    • v.34
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    • pp.73-82
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    • 2022
  • Purpose: The purpose of this study is to evaluate the effectiveness of reducing the absorbed dose to the ovaries and the quality of the CBCT image when using the HalcyonTM Fast kV CBCT of cervical cancer patients of child-bearing age who performed ovarian transposition Materials and Methods : Contouring of the cervix and ovaries required for measurement was performed on the computed tomography images of the human phantom (Alderson Rando Phantom, USA), and three Optically Stimulated Luminescence Dosimeter(OSLD) were attached to the selected organ cross-section, respectively. In order to measure the absorbed dose to the cervix and ovaries in the TruebeamTM pelvis mode (Hereinafter referred to as TP), The HalcyonTM Pelvis mode (Hereinafter referred to as HP) and The HalcyonTM Pelvis Fast mode (Hereinafter referred to as HPF), An image was taken with a scan range of 17.5 cm and also taken an image that reduced the Scan range to 12.5cm. A total of 10 cumulative doses were summed, It was replaced with a value of 23 Fx, the number of cervical cancer treatments, and compared In additon, uniformity, low contrast visibility, spatial resolution, and geometric distortion were compared and analyzed using Catphan 504 phantom to compare CBCT image quality between equipment. Each factor was repeatedly measured three times, and the average value was obtained by analysing with the Doselab (Mobius Medical Systems, LP. Versions: 6.8) program. Results: As a result of measuring absorbed dose by CBCT with OSLD, TP and HP did not obtain significant results under the same conditions. The mode showing the greatest reduction value was HPF versus TP. In HPF, the absorbed dose was reduced by 39.8% in the cervix and 19.8% in the ovary compared to the TP in the scan range of 17.5 cm. the scan range was reduced to 12.5 cm, absorbed dose was reduced by 34.2% in the cervix and 50.5% in the ovary. In addition, result of evaluating the quality of the image used in the above experiment, it complied with the equipment manufacturer's standards with Geometric Distortion within 1mm (SBRT standard), Uniformity HU, LCV within 2.0%, Spatial Resolution more than 3 lp/mm. Conclusion: According to the results of this experiment, HalcyonTM can select more various conditions than TruebeamTM in treatment of fertility woman who have undergone ovarian Transposition , because it is important to reduce the radiation dose by CBCT during radiation therapy. So finally we recommend HalcyonTM Fast kV CBCT which maintains image quality even at low mAs. However, it is consider that the additional exposure to low doses can be reduced by controlling the imaging range for patients who have undergone ovarian transposition in other treatment machines.

Influence of bearing surface angle of abutment screw on mechanical stability of joint in the conical seal design implant system (내부 원추형 연결형태 임플란트에서 지대주 나사머리의 좌면각도가 연결부 기계적 안정성에 미치는 영향)

  • Kim, Joo-Hyeun;Huh, Jung-Bo;Yun, Mi-Jung;Kang, Eun-Sook;Heo, Jae-Chan;Jeong, Chang-Mo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.30 no.3
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    • pp.206-214
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    • 2014
  • This study is to evaluate how different bearing surface angles of abutment screw affect the mechanical stability of the joint in the conical seal design implant system. Materials and Methods: Internal connection type regular implants, two-piece cemented type abutments and tungsten carbide/carbon-coated titanium alloy abutment screws were selected. Titanium alloy screws with conical ($45^{\circ}$) and flat ($90^{\circ}$) head designs which fit on to abutment were fabricated. The abutments were tightened to implants with 30 Ncm by digital torque gauge. The loading was applied once to the central axis of abutment. The mean axial displacement was measured using micrometer before and after the tightening and loading (n = 5). The abutment was tightened to implants with 30 Ncm and T-shape stainless steel crown was cemented. Then the change in the amount of reverse-torque was measured after the repeated loading to the central axis, and the place 5 mm away from the central axis. Compressive bending and fatigue strength were measured at the place 5 mm away from the central axis (n = 5). Results: Both groups showed the largest axial displacement when abutment screw tightening and total displacement was greater in the flat head group compared to conical head group (P < 0.05). However, there were no significant differences in reverse torque value, compressive bending and fatigue strength (P > 0.05). Conclusion: Within the limitations of this study, the abutment screw head design had no effect on two groups regarding the joint stability, however the conical head design affected the settlement of abutment resulting in the reduced total displacement.

Geochemistry and Genesis of Hydrothermal Cu Deposits in the Gyeongsang Basin, Korea : Hwacheon-ri Mineralized Area (경상분지내 열수동광상의 지화학 및 성인연구 : 화천리지역 광화대)

  • So, Chil-Sup;Choi, Sang-Hoon;Yun, Seong-Taek
    • Economic and Environmental Geology
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    • v.28 no.4
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    • pp.337-350
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    • 1995
  • The Hwacheon-ri mineralized area is located within the Cretaceous Gyeongsang Basin of the Korean peninsula. The mineralized area includes the Hwacheon, Daeweon, Kuryong and Cheongryong mines. Each of these mines occurs along copper-bearing hydrothermal quartz veins that crosscut late Cretaceous volcanic rocks, although some disseminated ores in host rocks also exist locally. Mineralization can be separated into three distinct stages (I, II, and III) which developed along preexisting fracture zones. Stage I is ore-bearing, whereas stages II and III are barren. The main phase of ore mineralization, stage I, can be classified into three substages (Ia, Ib and Ic) based on ore mineral assemblages and textures. Substage Ia is characterized by pyrite-arsenopyrite-molybdenite-pyrrhotite assemblage and is most common at the Hwacheon deposit. Substage Ib is represented by main precipitation of Cu, Zn, and Pb minerals. Substage Ic is characteristic of hematite occurrence and is shown only at the Kuryong and Cheongryong deposits. Some differences in the ore mineralization at each mine in the area suggest that the evolution of hydrothermal fluids in the area varied in space (both vertically and horizontally) with respect to igneous rocks relating the ore mineralization. Fluid inclusion data show that stage I ore mineralization mainly occurred at temperatures between ${\approx}350^{\circ}$ and ${\approx}200^{\circ}C$ from fluids with salinities between 9.2 and 0.5 wt.% eq. NaCl. In the waning period of substage Ia, the high temperature and salinity fluid gave way to progressively cooler, more dilute fluids of later substage Ib and Ic (down to $200^{\circ}C$, 0 wt.% NaCl). There is a systematic decrease in the calculated ${\delta}^{18}O_{H2O}$ values with paragenetic time in the Hwacheon-ri hydrothermal system from values of ${\approx}2.7$‰ for substage Ia, through ${\approx}-2.8$‰ for substage Ib, to ${\approx}-9.9$‰ for substage Ic. The ${\delta}D$ values of fluid inclusion water also decrease with decreasing temperature (except for the Daeweon deposit) from -62‰ (substage Ia) to -80‰ (substage Ic and stage III). These trends are interpreted to indicate the progressive cooler, more oxidizing unexchanged meteoric water inundation of an initial hydrothermal system which is composed of highly exchanged meteoric water. Equilibrium thermodynamic interpretation of the mineral assemblages with the variation in amounts of chalcopyrite through the paragenetic time, and the evolution of the Hwacheon-ri hydrothermal fluids indicate that the solubility of copper chloride complexes in the hydrothermal system was mainly controlled by the variation of temperature and $fo_2$ conditions.

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