Iron-overload can cause harmful effects such as cancer and aging via promoting the production of free radicals. The effect of orally administered nano-Fe overload with ascorbic acid on colon carcinogenesis was investigated in male ICR mice. After a 1-week acclimation, 5-week-old mice received three intraperitoneal injections (experimental week 0-2) of azoxymethane (AOM, 10 mg/kg body weight) weekly, followed by 2% dextran sodium sulfate (DSS) in drinking water for the next 1 week to induce aberrant crypt foci (ACF). Animals were divided into four groups; carboxymethylcellulose (CMC) alone (control), CMC + ascorbic acid (AA), CMC + nano-Fe (NFe), and CMC + NFe + AA groups. Animals were fed an AIN-76A purified rodent diet and daily administrated oral doses of 450 ppm each of nano-Fe and AA combination for 6 weeks. The colonic mucosa was stained with 0.5% methylene blue, and then the ACF and polyps were counted. Lipid peroxidation in the serum and liver was evaluated using the thiobarbituric acid-reactive substances (TBARS) assay. Iron concentration in the liver was measured using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). Iron concentration in the liver of the NFe-overloaded groups was higher than that of the control (p<0.05). AA treatment increased the iron concentration in the liver. The number of ACF was not significantly different among all the groups. The number of polyps in all the NFe-treated groups was slightly higher than that in the control group and AA only-treated group. The serum TBARS was not significantly different among all the groups, but that in the liver was higher in all the NFe-treated groups than it was in the control group (p<0.05). These results indicate that the additional NFe treatment did not affect the experimental colon carcinogenesis in mice regardless of the presence of ascorbic acid.
꽈리허리노린재는 가지과 및 메꽃과 기주에 피해를 주는 해충이다. 꽈리허리노린재는 실내의 25℃ 조건에서 1세대는 평균 76일정도 소요 되며, 성충으로 월동하기 때문에 수명이 길고, 일정한 주기 없이 알을 덩어리로 산란한다. 주로 잎 뒷면에 산란하며, 암컷 한 마리당 평균 195개, 최대 468개까지 산란하는 것으로 나타났다. 또한, 온도가 높아질수록 부화율은 높아지며, 발육기간은 짧아졌지만, 25℃를 제외한 다른 온도에서는 탈피율이 30%이하를 나타냈다. 위 결과를 토대로 선형모델로 추정한 결과 발육영점온도는 13.9℃, 유효적산온도는 526.3DD를 나타냈다. 고추재배지에서월동 성충이 6월 말 평균기온 25.7℃에서 나타나기 시작하여, 9월초에 가장 높은 밀도를 나타내었다. 부화한 개체들은 성충이 될 때까지 이동성이 적었으며 밀집하여 분포하였다. 집단을 형성하는 요인을 알아보고자 Net cage와 Y-tube olfactometer를 이용한 행동실험 결과, 암컷은 수컷과 암컷이 모두 있는 곳을 선택하였지만, 수컷은 암컷과 수컷이 모두 없는 곳을 선택하였다. 수컷이 새로운 기주를 찾아 정착하면, 암컷은 기주를 독점한 동종이 많이 있는 기주를 찾아가는 교미와 관련된 행동을 나타냈으며, 통신화합물의 영향은 알 수 없었다. 집단이 미치는 영향을 알아본 결과 꽈리허리노린재는 좁은 공간에서 집단으로 사육시 약충의 발육기간이 길고 우화율이 높아지는 반면, 개체 사육시 발육기간이 짧고, 우화율이 낮게 나타났다. 반면에 넓은 공간에서는 집단으로 사육 시 약충의 발육기간은 짧고 우화율은 낮게 나타났다.
The purpose of this research paper is to segment seafood market and find the factor and process that divide the segment market. Cluster analysis and in-depth interview was performed to identify meaningful segment market. The result of the research found three segment market such as seafood integration familiarity group, domestic seafood familiarity group, seafood unfamiliarity group. Seafood integration familiarity group is active consumer that consume both domestic and imported seafood at home. This group have high preference and familiarity about seafood. Seafood familiarity group purchase imported seafood for the reason that imported seafood is cheaper than domestic seafood and have similar quality level. Domestic seafood familiarity group consume mostly domestic seafood and not purchase imported seafood for the reason that imported seafood have low quality and safety. This group have high preference and familiarity about seafood. Seafood unfamiliarity group is low preference group about seafood and seldom eat at home. This study found that the main factor that divide segment market is seafood familiarity that formed by experiencing seafood in youth and seafood familiarity is main factor that determine consumption degree of seafood at home.
층면구조 안정성 다이어그램은 층면구조가 주어진 입도와 유속에서 나타나는 층면구조의 모양과 크기를 지시한다. 이 다이어그램은 대부분 수조실험에 의해 획득한 실험 데이터를 기반으로 작성되었다. 일반적으로, 수조실험은 입자의 크기와 유속사이의 관계를 이해하기 위해 분급이 좋고 단일입도의 분포를 보이는 퇴적물을 이용하여 수행되었다. 이 다이어그램에 의하면, 세립사와 중립사 퇴적물 표면에서 유속이 빨라지면서, 평행층에서 연흔이 형성되기 시작한다. 이 연구의 목적은 층면구조 안정성 다이어그램의 결과가 실험을 통하여 잘 재현되는지를 확인하고, 분급이 좋은 퇴적물과 달리 분급이 불량한 경우인 이정 입도 분포를 보이는 사질 퇴적물에서도 잘 재현되는지 확인하는 것이다. 본 연구 실험 결과는 2D 연흔이나 3D 연흔 층면구조가 형성되기 위해서, 분급이 불량한 퇴적물의 경우에, 분급이 좋은 퇴적물보다 더 높은 유체의 유속과 전단응력이 필요하다는 것을 보여주고 있다. 탄산염 퇴적물은 수력학적 분급작용이 활발하지 않으며, 퇴적물의 구성이 알로켐과 기질로 이루어지는 이정 입도 분포를 보이는 퇴적물로서 일반적으로 분급이 불량한 특징을 가지고 있다. 따라서, 실험의 결과는 탄산염 퇴적물에서 층면구조 형성을 위해 쇄설성 퇴적환경의 퇴적물 보다 더 높은 유속이 필요할 수 있음을 제안하고 있다. 분급이 불량한 퇴적물 입자가 침식되어 이동기 위해 더 높은 에너지와 유속이 필요하다는 것은 분급 효과, 마찰 효과, 안정성 효과, 갑옷 효과 등이 복합적으로 작용한 결과로 설명될 수 있을 것이다. 본 연구는 예비적 고찰로서, 이어지는 연구를 통해 이러한 현상을 과학적으로 설명하고 입도와 층면구조 형성의 상관성을 보다 정교하게 규명하고자 한다.
In this study, carbon dioxide (CO2) was used as an inhibitor of scale production on the surface of RO membrane. In order to compare the effects of CO2 injection on scale production, four RO modules: 1) without CO2 injection and anti-scalant (RO module #1), 2) with only CO2 injection (RO module #2), 3) with only anti-scalant (RO module #3), 4) with both CO2 injection and anti-scalant (RO module #4), were operated for 60 days under constant flux mode. The trans-membrane pressure (TMP) was observed to decrease significantly in RO modules with CO2 injection as compared with the other RO modules. When the feed water pH was controlled at 5.0 by injecting CO2, the maximum TMP in RO modules #2 and #4 was founded to decrease by 42 aㅋnd 40%, respectively. Moreover, the Ca2+ concentration in the concentrate was 20mg/L lower in RO modules without CO2 injection which is attributed to the scale formation on the surface of the RO membranes. The SEM-EDS analysis further showed a serious fouled RO membrane surface in RO modules #1 and #3.
Gas hydrates are crystalline solids in which gas molecules (guests) are trapped in water cavities (hosts) that are composed of hydrogen-bonded water molecules. During the formation of gas hydrates in seawater, the equilibria and kinetics are then affected by salinity. In this study, the effects of salinity on the equilibria of CO2 and R134-a gas hydrates has been investigated by tracing the changes of operating temperature and pressure. Increasing the salinity by 1.75% led to a drop in the equilibrium temperature of about 2 oC for CO2 gas hydrate and 0.38 oC for R-134a gas hydrate at constant equilibrium pressure; in other words, there were rises in the equilibrium pressure of about 1 bar and 0.25 bar at constant equilibrium temperature, respectively. The kinetics of gas hydrate formation have also been investigated by time-resolved in-situ Raman spectroscopy; the results demonstrate that the increase of salinity delayed the formation of both CO2 and R134-a gas hydrates. Therefore, various ions in seawater can play roles of inhibitors for gas hydrate formation in terms of both equilibrium and kinetics.
This study aims to understand the their characteristics and analyze the diverse landscape plants distributed in the traditional temples. We surveyed the landscape plants that the planting species around building and terraced flower bed, excluded the spontaneous species. The contents of analysis were form, leaf fall and type, exotic species and the Buddhist symbol plant. Mostly, the families of landscape plants that rosaceae, compositae and liliaceae were much used. The rosaceae were used in landscape planting, and compositae and liliaceae were used in terraced flower bed and flower garden. Especially, a single planting, a linear planting and symmetrical planting most occupied in the planting types. This reason seemed the object and function of religion. There were lots of trees and shrubs in the form, and they were main material for formation of landscape and frame. Therefore, the temple landscape was composed of landscape plants and planting types and fell into chime with these components. The deciduous broad leaved was many in the leaf fall and type. The aesthetic value is a deciduous broad leaved directed by the external features of nutrition and reproductive organs with plants and flowers, recording, leaves, fruits, and non-seasonal forms along with the variety of landscapes inspectors by providing visual variety, because expression. Exotic species were introduced intentionally, unintentionally for a variety of purposes in a foreign species, naturalized plants invasive species was the wild country to adapt to the environment. Exotic materials will have to be rejected unconditionally, but indiscriminate use of space in a traditional review of the planting material is necessary because of the high potential to inhibit and distort the traditional landscape. Buddhist symbol plant is a very important feature as plants that have the least Buddhist doctrine and has a meaning and a symbol representing the Buddhist, the inspectors can show the difference with other scenic areas.
포항시 마이오세 두호층에서 2개의 신생대 어류 화석들이 발견되었다. 두호층에서 발견된 이 어류 화석들은 다 음과 같은 근거로 도다리속으로 동정되었다. 첫째, 앞쪽 등지느러미가 두개부 위까지 연장되어 뻗어있다. 둘째, 두개골 에서 안와는 모두 오른쪽에 몰려있는 비대칭성을 갖는다. 셋째, 낚시 바늘 모양의 미설골을 지닌다. 넷째, 미설골의 좌 골부가 꺾여있다. 다섯째, 후의쇄골이 존재한다. 여섯째, 척추체의 개수가 27개를 넘는다. 일곱째, 첫 번째 뒷지느러미 담기골이 연장되어 있다. 여덟째, 미설골의 내연부가 ‘c’자 형태를 갖는다. 아홉째, 분문돌기가 작거나 거의 없다. 열째, 몸에 여러 반점들이 존재한다. 도다리속 어류 화석은 동아시아에서 최초로 보고되는 것이다. 두 표본은 두개골의 비대 칭성과 납작한 정도에서 해부학적 차이가 존재한다. 이는 가자미과 어류의 독특한 개체발생 단계를 나타내는 데, 그들 은 표영성 생활 양식에서 저서성 생활 양식으로 전환할 때 위와 같은 해부학적 차이를 수반하기 때문이다.
우박 및 태풍에 의해 생육기간 동안에 낙엽이 발생했을 때를 가정하여 5월부터 10월까지 1개월 간격으로 인위적으로 낙엽 처리를 실시하고 그에 따른 사과나무 ‘시 나노스위트’의 수량, 저장양분 및 다음해 화총 수에 미치는 영향을 조사하였다. 평균 과중은 낙엽 정도가 심할수록, 낙엽 시기가 빠를수록 감소하였으며 과실 비대 감소는 수량 감소로 이어졌다. 30% 낙엽구의 과실 크기 및 수량은 낙엽 시기와 관계없이 무처리구와 유의한 차이를 보이지 않았다. 2년생 가지의 탄수화물 함량은 8월 이전 낙엽구가 9월이후 낙엽구에 비해 현저히 낮은 함량을 보여 낙엽 정도보다는 낙엽 시기의 영향이 컸다. 8월 이전 낙엽구 중에서는 낙엽 시기가 늦어질수록 탄수화물 함량이 감소하여 8월 낙엽구에서 무처리구 대비 50% 수준으로 가장 낮았다. 생육기 중의 조기 낙엽 다음해 화총 수는 낙엽 시기 및 정도에 따라 큰 차이를 보였다. 5월 이후 낙엽 시기가 늦어질수록 화총 수가 감소하여 7월 낙엽 구에서 가장 낮은 화총 수를 보였으며 8월 이후 낙엽구는 무처리구와 큰 차이를 보이지 않았다. 낙엽 이듬해 화총 수는 수체내 탄수화물 함량과 정의 상관을 보였다. 위의 결과, 7월 이전의 낙엽 피해가 발생되었을 때에는 적과를 통해 개별 과실의 sink 기능을 강화하여 과실 비대를 향상시키고, 저장양분 확보를 통해 다음해 화총 수를 확보하는 것이 필요할 것으로 판단된다.
Shenyang was one of the representative transportation hub of Northeast China during the modern period. The formation and development of the railway network gave great influence on Shenyang’s city development. In order to understand the relationship between railway and city development, first, we classified Shenyang’s city development period by the railway network’s formation and expansion process. Then, we analyzed the relationship between railway and city space by five categories. The results of this study are as follows. First, before railway was constructed, Shenyang was a castle city, which also was the economic center of Northeast China. This was the main reason Shenyang was chosen as a railway zone. During the modern period, the castle structure became an obstacle to city transportation and environment, therefore, it was disposed. During the period of railways’ expansion, South Manchuria, Jingfeng and Shenhai railway line was constructed in Shenyang. Since each line had different operation organizations, city sites along the railways were planned separately. However, these operation organizations had one common purpose, which was to use railway as an accelerator for economic development. During the period of railway’s military usage, railway was reorganized as military supply transport for the Japanese, which also was used as a tool for the expansion of colonialism. Second, after Shenyang’s city space was reconstructed along the railway, it created a close connection with city structure, city facilities, landscape and city transportation system. Hence, the railway system played a key role in modern city planning.