• Journal of the Mineralogical Society of Korea
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• v.26 no.1
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• pp.55-64
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• 2013

The generation of staurolite from the mixed-phase muscovite and the metamorphic environment of shales in the Baekunsa formation, Hongsan, Buyeo, were studied using electron probe micro analysis (EPMA). The average chemical composition of mica-type mineral is $(K_{1.11}Na_{0.26}Ca_{0.04})(Al_{3.93}Fe_{0.21}Mg_{0.07})(Si_{6.08}Al_{1.92})O_{20}(OH)_4$, and shows a characteristics of the so-called illite with a low content of interlayer cations and Fe, Mg in octahedral sites. The mica-type mineral shows a typical chemical composition of the mixed-phase among muscovite, pyrophyllite, and chlorite (mixed-phase muscovite, $Mu_{70.5}Py_{23.5}Ch_{6.0}$). The staurolite, in general, occurs with the mixed-phase muscovites, pyrophyllites, and aluminosilicates in the rock. We consider that staurolite can be formed by a reaction involving pyrophyllite such as pyrophyllite+chloritoid. The chloritoid is formed by a reaction between pyrophyllite and chlorite and is supposed to be used up in the process of staurolite formation. As a result, the mixed-phase muscovite, formed during the transition of illite to muscovite, plays an important role for the generation of the staurolite. Considering that the reaction occurs at the temperature higher than $300^{\circ}C$ and pyrophyllites transform into aluminosilicates at $350^{\circ}C$, the shale in the Baekunsa formation can be considered to have been experienced a metamorphic temperature between $300{\sim}350^{\circ}C$.

• Journal of Preventive Medicine and Public Health
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• v.31 no.1 s.60
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• pp.15-26
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• 1998

p53 is the most frequently mutated gene in female breast cancer tissues and the prognosis of breast cancer could be changed by mutation of the gene. This study was performed to examine risk factors for breast cancer subtypes classified by p53 mutation and to investigate the roles of p53 gene mutation in carcinogenesis of breast cancer. The study subjects were 81 breast cancer patients and 121 controls who were matched to cases 1:1 or 1:2 age, residence, education level and menopausal status. All the subjects were interviewed by a well-trained nurse with standardized questionnaire on reproductive factors, and wire asked to fill the self-administrative food frequency questionnaire. p53 gene mutation in the cancer tissue was screened using polymerase chain reaction (PCR)-single strand conformational polymorphism (SSCP) method. Mutation type was identified by direct sequencing of the exon of which mobility shift was observed in SSCP analysis. Mutations were detected in p53 gene of 25 breast cancer tissues. By direct sequencing, base substitutions were found in 20 cancer tissues (10 transition and 10 transversion), and frame shift mutations in 5 (4 insertions and 1 deletion). For the whole cases and controls, risk of breast cancer incidence decreased when the parity increased, and increased when intake amount of total calory, fat, or protein increased. Eat and protein were statistically significant risk factors for breast cancer with p53 mutation. For breast cancer without p53 mutation, protein intake was the only significant dietary factor. These results suggest that causes of p53 positive breast lancer would be different from those of p53 negative cancer, and that dietary factors or related hormonal factors induce mutation of p53, which may be the first step of breast cancer development or a promoter following some unidentified genetic mutations.

• The Journal of Engineering Geology
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• v.25 no.2
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• pp.215-225
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• 2015

We performed injection tests in a deep-seated confined aquifer to assess the potential of artificial recharge as a means of preventing saltwater contamination, thereby securing groundwater resources for the Nakdong Delta area of Busan City, Korea. The study area comprises a confined aquifer, in which a 10-21-m-thick clay layer overlies 31.5-36.5 m of sand and a 2.8-11-m-thick layer of gravel. EC logging of five monitoring wells yielded a value of 7-44 mS/cm, with the transition between saline and fresh water occurring at a depth of 15-38 m. Above 5 m depth, water temperature is 10-15.5℃, whereas between 5 and 50 m depth the temperature is 15.5-17℃. Approximately 950 m³ of fresh water was injected into the OW-5 injection well at a rate of 370 m³/day for 62 hours, after which the fresh water zone was detected by a CTD Diver installed at a depth of 40 m. The persistence of the fresh water zone was determined via EC and temperature logging at 24 hours after injection, and again 21 days after injection. We observed a second fresh water zone in the OW-2 well, where the first injection test was performed more than 20 days before the second injection test. The contact between fresh and saline water in the injection well is represented by a sharp boundary rather than a transitional boundary. We conclude that the injected fresh water occupied a specific space and served to maintain the original water quality throughout the observation period. Moreover, we suggest that artificial recharge via long-term injection could help secure a new alternative water resource in this saline coastal aquifer.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.153-168
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• 2000

An estuarine marsh is semi -inclosed inlets, located between coastal and terrestrial environment. The sediment transport by river and tide through tidal river and vertical accretion by sediment accumulation are important processes in estuarine marsh. An analysis of the vertical accretion rate at various time scale is important work for understanding and managing coastal environments. The purpose of this study is to determin the spatial characteristics of vertical accretion rate in an estuarine marsh, Sunchon Bay, in the southern coastal region of Korean peninsula. The methods of analysis are sedimentation rate by individual tidal cycle, annual accretion rate, concentration of total suspended load in water column. Spatial characteristics of sedimentation rate by individual tidal cycle was investigated using 30 filter paper traps. Sedimentation rate by individual tidal cycle at levee edge was higher than that at back marsh. The sedimentation rate decreased with distance from estuarine front. Levee effect and proximity to the turbidity maximum zone result in a higher sedimentation rate in the levee edge. There is a weak relation-ships between tidal regime and sedimentation rate by individual tidal cycle. Spatial cahracteristics of annual accretion rate was investigared using 30 artificial marker plots. Annual accretion rate at back marsh($1.5{\sim}3.5cm/yr$) was higher than that at tidal river levee edge($0.8{\sim}3.0cm/yr$). Total suspended load (TSL) concentrations in water column also indicate this spatial characteristics of annual accretion rate. TSL concentration in water column leaving the vegetation part dramatically decreased. There is a very strong relationship between the concentration of suspended load and accretion rate. These results indicate that annual accretion rate is controlled by vegetation cover and proximity to the turbidity maximum zone. This difference of spatial characteristics of vertical accretion rate ar various time-scale was due to the fact that surface sediment of levee edge was eroded by tide and other factors. The major findings are as follows. First, the spatial characteristics of vertical accretion rate are different from various time-scale. Second, the major mechanism for the vertical accretion rate in this region is suspended load trapping by vegetation. Third, this region is primarily a depositional regime over the time-scale of the present data Fourth, this estuarine marsh is accreting at rates beyond other area.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.511-525
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• 2003

The Okcheon Group in the southwestern part of the Okcheon Metamorphic Belt is subdivided into two distinct tectonostratigraphic units: the Boeun unit in the south and the Pibanryeong unit in the north. The Boeun unit consists of petites, psammites, carbonaceous petites, limestones and pebble-bearing quartzites. The Pibanryeong unit is composed of petites, well-sorted fine-grained psammites, carbonaceous psammites and quartzites. In order to outlining stratigraphy and depositional environments of the Okcheon Group, detailed stratigraphic sections were measured in three locations; one section(Gosan section) of the Boeun unit and two sections(Sorungjae and Hwangryeongzae sections) of the Pibanryeong unit. The Gosan section of the Boeun unit is interpreted to be deposited in the shallow marine environments, whereas the Sorungjae and Hwangryeonaiae sections of the Pibanryeong unit appear to be deposited in slope and deep basin environments. This result indicates rapid subsidence between deposition of the Boeun and Pibanryeong units in sedimentary environment. The trace of sedimentological environments in the Hwasan area was investigated by geochemical analysis of 109 metapelitic and psammitic rock samples. Distinct chemical variations of politic and psammitic rocks from the Boeun and Pibanryeong units in the study area are evident from plots of major elements and $A1_2O_3$/$SiO_2$ versus Basicity Index($Fe_2O_3{＋}MgO$)/($SiO_2{＋}K_2O{＋}Na_2O$). The rocks show a progressive chemical trend from the Boeun unit to the Pibanryeong unit on these diagrams. They in the southern sector of the Boeun unit display lower values and a comparatively wide range of $A1_2O_3$/$SiO_2$ and Basicity Index, as compared with those from the northern sector of the Boeun and Pibanryeong units. The southern sector of the Pibanryeong unit including narrow staurolite-bearing zone is characterized by values that are transitional between the Boeun and Pibanryeong units. These data, combined with depositional environment progressively deepened towards the northwest, support a half-graben model for the Okcheon basin, as proposed by Cluzel et al.(1990)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.666-672
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• 1997

Twenty years' daily mean air temperature data was used to calculate the critical early seeding date(CESD), the optimum heading date(OHD), the critical late heading date for stable ripening(CHDR) and the critical late ripening date(CLRD) for rice seeded on dry paddy in different agroclimatic zones in Korea. The CESD was defined as the first day with mean air temperature of 13$^{\circ}C$, and the OHD as the first day of the 40 consecutive days with mean air temperature of 22$^{\circ}C$ or above after heading. The CHDR was defined as the date after which the cumulative daily mean air temperature would be at least 76$0^{\circ}C$. Lastly, the CLRD was defined as the last day when daily mean air temperature remains above 15$^{\circ}C$. This information was used for the estimation of periods from the earliest date of seeding to optimum heading date, the latest possible date of heading and the latest possible date of ripening in respective regions. For instance, in Suwon, those respective periods mentioned were found to be 104days, 124days, and 165days.

• Journal of the Mineralogical Society of Korea
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• v.13 no.1
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• pp.1-14
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• 2000

알루나이트는 포항지역의 제3기 연일층군의 이암 층내의 탄산염 결핵체 주변에서 할로이사이트와 함께 극미립 변질물 (1-2 $\mu\textrm{m}$)로서 산출된다. 알루나이트는 정육면체와 유사한 능면체 결정형을 이루고 침상 내지 단주상의 할로이사이트와 밀접한 공생관계를 이룬다. X-선회절 분석에 의해서 이 알루나이트는 a=6.9897(1) $\AA$, c=17.2327(4)$\AA$, V=728.75(3) $\AA$3의 격자상수값을 갖는 것으로 밝혀졌다. X-선형광된 이 알루나이트의 화학식은 (K0.94N0.06)(Al2.55Fe3+0.45)(SO4)2(OH)6 으로서, 나트로알루나이트 단성분을 6-7 mole%정도 함유하는 것으로 분석되었다. 또한 시차열분석 (TG-DTG-DTA)을 통해서 알루나이트의 승화성 성분들 (H2O와 SO3)의 존재와 함유 정도를 조사하였고, 고온X-선회절분석을 병행하여 이 광물의 OH기의 이탈 반응 (52$0^{\circ}C$)과 고온상으로의 전이 반응 ($600^{\circ}C$ 및 $700^{\circ}C$)을 감정 하였다. K/Ar 법으로 측정된 알루나이트의 생성 연대 ($0.342\pm$0.008 Ma)와 안정동위원소들의 분석 결과 ($\delta$18Oso4=-1.7, $\delta$DSMOW=-31, $\delta$34S=-10.8)는 이 알루미늄 황산염 광물이 연일충군의 융기 이후에 야기된 민물의 유입에 의한 표성기원의 변질작용의 결과로 생성되었음을 지시한다. 알루나이트+할로이사이트 공생군의 침전은 이암 내에서 조성된 강산성 (pH=2-3)의 알루미늄 황산염 용액이 탄산염 결핵체를 만나 반응하여 pH가 국지적으로 증가되어 (pH=4) 과포화되는 과정에 의해서 야기되었다. 컴퓨터를 이용한 Al3+의 포화지수에 관한 화학적 평형 모델링 실험 결과, 알루미늄 황산염 용액으로부터의 알루나이트와 할로이사이트의 침전은 pH=4 및 \ulcornerSO42-=10-4M 조건에서 K+과 Si(OH)4의 농도가 10-4M 이상 유지되어야 가능한 것으로 밝혀졌다.

• The Journal of Engineering Geology
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• v.19 no.2
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• pp.165-175
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• 2009

This study is concerned with creep characteristics of red shale in the Haman Formation by the single stage and multi stage loading tests. Creep constants in the Griggs's experiential equation, ${\epsilon}_t$= a+$b{\cdot}log$ t + $c{\cdot}t$, are determined by regression analysis on the total data obtained. The transition time between the primary and second creep means the time when the differential value of $b{\cdot}log$ t is equal to the differential value of $c{\cdot}t$. The correlation equation between loads (${\sigma}$%) and creep constants is deduced from the three times multi stage loading tests. Also a failure time under each loads is anticipated from creep constants and maximum strain at the failure.

• Journal of Wetlands Research
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• v.10 no.1
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• pp.49-57
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• 2008

Tidal flat, classified as wetland of coastal zone, is critical transitional zone connecting sea with land, and fulfills a variety of functions necessary for maintaining coastal ecosystem. Although it is critical to protect and strengthen its functions of coastal wetlands, tidal flat has been mainly viewed as areas for development in Korea. Therefore, this study provides with the effective mitigation measures so as to minimize adverse impacts of tidal flat reclamation projects on the proper environmental values. So far, coastal development has not considered as important the fact that development site consists of tidal flat in site selection. Therefore, large scale of tidal flats was abused. Problems were emerged only after tidal flat development was already planned. The original plan had to be revised. To rectify the problem, impacts of development on the environment need to be discussed based on the initial development planning. Particularly, sandy beaches, rocky shores and shallow areas, underwater forest including seagrass beds as well as the tidal flat in good condition should be excluded from development site.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3412-3416
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• 2010

The purpose of this study was attempted to identify the effect of physical function on operative treatment of colorectal cancer patients. Colorectal cancer patients(110 persons) who visited a general hospital in Seoul were examined with questionnaires and interview from December 15, 2009 to January 30, 2010. The results of this study are as follows ; First, operative treatment side-effects were significantly higher in patients before ileostomy repair than in patients after ileostomy repair(t=5.284, p<0.001). Secondly, sexual satisfaction were higher in pre-operative radiotherapy patients than in post-operative radiotherapy patients(t=1.946, p<0.05). Thirdly, micturition problems were significantly higher in discomfort symptom of stoma patients than in nonstoma patients(t=1.537, p<0.05). In conclusion, in order to improve physical function on operative treatment of colorectal cancer patients, it is necessary to develop intervention program about the improvement of function status and discomfort symptoms.