• 대한치과교정학회지
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• 제36권1호
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• pp.55-62
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• 2006

교정용 미니임플랜트는 작은 크기로 삽입 부위에 제한이 적어 고정원 조절에 널리 이용되고 있다. 그러나 잦은 탈락의 단점이 있어 초기 안정성을 향상시키기 위한 다양한 형태와 길이에 관한 연구가 시도되어왔다. 이 연구의 목적은 교정용 미니임플랜트의 형태와 길이에 따른 초기 안정성에 대한 기계역학적 성질을 비교 분석하는 것이다. 미니임플랜트의 직경은 1.6 mm였으며, 형태는 원통형과 원추형, 길이는 6 mm와 8 mm로 구성되어 원통형 6 mm, 원통형 8 mm, 원추형 6 mm, 원추형 8 mm군과, 중앙 1/2에서부터 상방으로 나사산이 점차적으로 작아지는 변형된 원추형 8 mm군을 포함하여 총 5군으로 구성되었다. 각 군은 10개의 미니임플랜트로 구성되었고, 균일한 밀도의 polyurethane foam에 삽입 후 제거하였다. 시간에 따른 삽입 및 제거 토크의 변화와 각각의 최대 토크 등을 측정하여 기계역학적 성질을 비교 분석하였다. 동일한 길이에서 원추형은 삽입과 제거 시 원통형보다 유의성 있게 더 큰 토크를 보여주었다 (p<0.001). 동일한 형태에서 삽입과 제거 시 긴 미니임플랜트가 짧은 미니임플랜트보다 유의성 있게 더 큰 토크를 보여주었다 (p<0.001). 원추형 6 mm는 원통형 8 mm에 비해 삽입 시 유의성 있게 낮은 토크를(p<0.001) 보여주었지만, 제거 시 비슷한 토크를 보여주었다. 변형된 원추형 8 mm에서는 최대 제거 토크 후 지속적으로 높은 제거 토크를 보여주었다. 미니임플랜트의 초기 안정성은 원추형에 의해 향상될 수 있으며, 상부 나사산의 작은 크기와 형태는 미니임플랜트의 초기 안정성에 긍정적인 영향을 미치는 것으로 보인다.$76^{\circ}$였다. Naso frontal angle (G-N'-Pn)은 남자 $142^{\circ}$, 여자 $147^{\circ}$, transverse nasal prominence (Zy(Rt)-Pn-Zy(Lt))는 남자 $112^{\circ}$, 여자 $116^{\circ}$로 남녀 간에 통계학적으로 유의차가 있었다 (p<0.05). 하안면고경 하방 2/3 (Li-Me')와 하악체길이(Go'-Me'), 입술고경(ULPm-Li)과 폭경(Ch(Rt)-Ch(Lt))의 비율은 각각 2/5로 나타났다. 관상기준평면에서 안면의 윤곽을 나타내는 계측점인 FT, Zy, Pn, ULPm, Li, Me'까지의 거리의 비는 -1/-1/1/0.5/0.5/-0.6였다. 또한 얻어진 자료를 이용하여 한국 성인 정상교합자의 3차원 안면 모델을 제작하였으며 이는 교정진단 또는 치료결과 비교 시 template로 활용될 수 있으리라 사료된다.이상의 결과로 극체 방출란만을 선별하여 $12{\sim}36$시간 사이에 분할하는 난자들만을 선별하여 배양한다면 배발생능을 가진 난자들의 비율을 높일 수 있을 것으로 사료된다. 균주(菌株)의 형태학적(形態學的) 배양학적(培養學的) 특성(特性)을 조사(調査)한 결과(結果) Candida guilliermondii var. guilliermondii 로 동정(同定)되었다. 6. CHS-13 균주(菌株)를 당화액(糖化液)에 배양(培養)시켰을 때 Lowry-protein 함량은 $0.72\;mg/m{\ell}$ 이었으며 ,

• Parasites, Hosts and Diseases
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• 제54권3호
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• pp.281-289
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• 2016

Clonorchis sinensis is a Group-I bio-carcinogen, associated with cholangiocarcinoma (CCA). The hamster is the only experimental model of C. sinensis-mediated CCA, but we oblige another animal model. The present study intended to develop a C. sinensis (Cs) mediated CCA model using C3H/He mice, co-stimulated with N-nitrosodimethylamine (NDMA) and dicyclanil (DC). The mice were divided into 8 groups with different combinations of Cs, NDMA, and DC. Six months later the mice were sacrificed and subjected to gross and histopathological examination. The body weights were significantly reduced among the groups treated with 2 or more agents (eg. Cs+NDMA, Cs+DC, NDMA+DC, and Cs+NDMA+DC). In contrast, liver weight percentages to body weight were increased in above groups by 4.1% to 4.7%. A Change of the spleen weight was observed only in Cs+NDMA group. Though C. sinensis infection is evident from hyperplastic changes, only 1 worm was recovered. Two mice, 1 from Cs and the other from Cs+DC group, showed mass forming lesions; 1 ($281.2mm^3$) from the Cs group was a hepatocellular adenoma and the other ($280.6mm^3$) from the Cs+DC group was a cystic mass (peliosis). Higher prevalence of gray-white nodules was observed in Cs group (42.9%) followed by Cs+NDMA+DC group (21.4%). The mice of the Cs+NDMA+DC group showed hyper-proliferation of the bile duct with fibrotic changes. No characteristic change for CCA was recognized in any of the groups. In conclusion, C3H/He mice produce no CCA but extensive fibrosis when they are challenged by Cs, NDMA, and DC together.

• 한국초지조사료학회지
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• 제34권3호
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• pp.193-201
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• 2014

This study was conducted to examine the effects of defaunation (removal of live protozoa) on fermentation characteristics, degradation of ryegrass hay and $CH_4$ (methane) production by rumen microbes when incubated with plant oils (SO, sunflower oil and LO, linseed oil) in vitro. Sodium lauryl sulfate (0.000375 g/ml) as a defaunation reagent was added into the culture solution and incubated anaerobically up to 24 h at $39^{\circ}C$. pH from defaunation was increased for all treatments from 6 h incubation times (p<0.01-0.001) compared with those from fauantion. Concentration of ammonia-N from defaunation is higher than that from faunation at 3 h (p<0.001), 12 h (p<0.05) and 24 h (p<0.001) incubation times. Defaunation decreased (p<0.01-0.001) total volatile fatty acid concentration at all incubation times. Molar proportions of $C_2$ (acetate, p<0.05-0.001) and butyrate (p<0.01-0.001) were also decreased by defaunation at all incubation times. Molar proportion of $C_3$ (propionate), however, was increased by defaunation at all incubation times (p<0.001). Thus the rate of $C_2$ to $C_3$ was decreased by defaunation at all incubation times (p<0.001). Defaunation decreased ED (effective degradability) of dry matter (p<0.001) and ED of neutral detergent fiber (p<0.001) of ryegrass hay. Defaunation decreased total gas, $CH_4$ production, $CH_4$ % in total gas and $CH_4/CO_2$ at all incubation times (p<0.001). Oil supplementation decreased total gas (p<0.05-0.001), $CH_4$ production (p<0.001) and $CH_4$ % in total gas (p<0.001) compared with control at all incubation times. The result of this study showed that defaunation combined with oil supplementation may cause an alteration of microbial communities and further medicate the fermentation pattern, resulting in both reduction of degradation of ryegrass hay and $CH_4$ production. No difference, however, was observed in all the examinations between SO and LO.

• 한국임상수의학회지
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• 제24권2호
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• pp.225-228
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• 2007

개 추간판 디스크 2 증례(症例)를 대상으로 봉독약침 및 봉독약침과 한약제로 각각 치료하였다. 증례(症例) 1은 흉-요추부 추간판탈출증(T11-T12, T12-T13, L3-L4 및 L4-L5)으로 진단(診斷)된 증례이었으며. 증례 2는 흉추부 추간판탈출증(T10-T11 및 T12-T13)으로 진단(診斷)된 증례이었다. 이들 증례에 대하여 봉독약침(0.1 ml/혈위, 총$200{\mu}g$)을 실시(實施)하였으며, 운동요법과 수영요법도 병용하였다. 봉독약침에 사용한 혈위는 GV20-Bai Hui, GB30-Huan Tiao, ST36-Zu San Li, GB34-Yang Ling Quan, ST40-Feng Long, ST41-Jie Xi 및 BL40-Wei Zhong, 병변부 및 압통점이었다. 또한 증례 2에 대하여는 봉독약침과 더불어 Zheng Gu Zi Jin Dan(정골자금단(正骨紫金丹) : 1 g), Shiuh Duann(속단(續斷) .0.2 g), Du Zhong(두중(杜仲) : 0.2 g), Mo Yao(몰약(沒藥 : 0.2 g), Ru Xiang(유향(乳香) : 0.2 g) 및 Pyrite(자연동(自然銅) : 0.2 g)를 각각 총 9일간 경구투여(2회/1일)하였다. 증례 1은 총 4주간 11회 치료, 증례(症例) 2는 총 2주간 6회 치료 후 각각 보행이 가능하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 제3회 최신 분말제품 응용기술 Workshop
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• pp.25-37
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• 2002

The most important industrial application of gamma radiation in characterizing green compacts is the determination of the density. Examples are given where this method is applied in manufacturing technical components in powder metallurgy. The requirements imposed by modern quality management systems and operation by the workforce in industrial production are described. The accuracy of measurement achieved with this method is demonstrated and a comparison is given with other test methods to measure the density. The advantages and limitations of gamma ray densitometry are outlined. The gamma ray densitometer measures the attenuation of gamma radiation penetrating the test parts (Fig. 1). As the capability of compacts to absorb this type of radiation depends on their density, the attenuation of gamma radiation can serve as a measure of the density. The volume of the part being tested is defined by the size of the aperture screeniing out the radiation. It is a channel with the cross section of the aperture whose length is the height of the test part. The intensity of the radiation identified by the detector is the quantity used to determine the material density. Gamma ray densitometry can equally be performed on green compacts as well as on sintered components. Neither special preparation of test parts nor skilled personnel is required to perform the measurement; neither liquids nor other harmful substances are involved. When parts are exhibiting local density variations, which is normally the case in powder compaction, sectional densities can be determined in different parts of the sample without cutting it into pieces. The test is non-destructive, i.e. the parts can still be used after the measurement and do not have to be scrapped. The measurement is controlled by a special PC based software. All results are available for further processing by in-house quality documentation and supervision of measurements. Tool setting for multi-level components can be much improved by using this test method. When a densitometer is installed on the press shop floor, it can be operated by the tool setter himself. Then he can return to the press and immediately implement the corrections. Transfer of sample parts to the lab for density testing can be eliminated and results for the correction of tool settings are more readily available. This helps to reduce the time required for tool setting and clearly improves the productivity of powder presses. The range of materials where this method can be successfully applied covers almost the entire periodic system of the elements. It reaches from the light elements such as graphite via light metals (AI, Mg, Li, Ti) and their alloys, ceramics ($AI_20_3$, SiC, Si_3N_4, $Zr0_2$, ...), magnetic materials (hard and soft ferrites, AlNiCo, Nd-Fe-B, ...), metals including iron and alloy steels, Cu, Ni and Co based alloys to refractory and heavy metals (W, Mo, ...) as well as hardmetals. The gamma radiation required for the measurement is generated by radioactive sources which are produced by nuclear technology. These nuclear materials are safely encapsulated in stainless steel capsules so that no radioactive material can escape from the protective shielding container. The gamma ray densitometer is subject to the strict regulations for the use of radioactive materials. The radiation shield is so effective that there is no elevation of the natural radiation level outside the instrument. Personal dosimetry by the operating personnel is not required. Even in case of malfunction, loss of power and incorrect operation, the escape of gamma radiation from the instrument is positively prevented.

• 한국식품저장유통학회지
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• 제19권4호
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• pp.463-469
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• 2012

전복가공부산물인 내장의 이용가치를 향상시키고자 열수추출, 에탄올추출 등의 방법으로 유효성분을 추출하고 항산화 및 항피부노화 활성을 측정하였다. DPPH 라디칼소거능 분석결과 Tris-HCl 추출물은 $58.60{\pm}0.88%$으로 높은 라디칼소거능을 보였으며, 다음으로 에탄올추출물은 $55.40{\pm}0.62%$의 라디칼소거능을 보였다. Anti-elastase활성을 분석한 결과 에탄올추출물이 다른 시험구에 비하여 현저하게 높은 활성을 보였다. 전복내장추출물의 세포독성을 확인하기 위하여 human dermal fibroblast 세포에 대하여 MTT 시험결과 세포독성은 전혀 나타나지 않았다. 에탄올 추출물의 농도를 달리하여 human dermal fibroblast 세포에 대해pro-collagen type I 생합성능시험결과 10.0 ${\mu}g/mL$에서 $705.30{\pm}3.06$ ng/mL로 retinoic acid $453.60{\pm}2.82$ ng/mL보다 우수한 결과를 보였다. MMP-1 활성은 10 ${\mu}g/mL$에서 $45.30{\pm}0.80$ ng/mL를 보여 control의 $62.37{\pm}0.56$ ng/mL 보다 감소정도가 낮았다. 본 연구는 전복내장추출물의 항산화와 항노화활성에 관하여 최초로 시도되었으며 향후 전복내장을 이용한 다양한 연구의 기초자료로서 중요한 의미가 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권10호
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• pp.1381-1388
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• 2012

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, $CH_4$ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at $39^{\circ}C$. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and $CO_2$ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). $CH_4$ production was higher from faunation than from defaunation at all incubation times (p<0.05).

• Plant Biotechnology Reports
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• 제4권3호
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• pp.213-222
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• 2010

Within their natural habitat, crops are often subjected to drought and heat stress, which suppress crop growth and decrease crop production. Causing overaccumulation of glycinebetaine (GB) has been used to enhance the crop yield under stress. Here, we investigated the response of wheat (Triticum aestivum L.) photosynthesis to drought, heat stress and their combination with a transgenic wheat line (T6) overaccumulating GB and its wild-type (WT) Shi4185. Drought stress (DS) was imposed by controlling irrigation until the relative water content (RWC) of the flag leaves decreased to between 78 and 82%. Heat stress (HS) was applied by exposing wheat plants to $40^{\circ}C$ for 4 h. A combination of drought and heat stress was applied by subjecting the drought-stressed plants to a heat stress as above. The results indicated that all stresses decreased photosynthesis, but the combination of drought and heat stress exacerbated the negative effects on photosynthesis more than exposure to drought or heat stress alone. Drought stress decreased the transpiration rate (Tr), stomatal conductance (Gs) and intercellular $CO_2$ concentration (Ci), while heat stress increased all of these; the deprivation of water was greater under drought stress than heat stress, but heat stress decreased the antioxidant enzyme activity to a greater extent. Overaccumulated GB could alleviate the decrease of photosynthesis caused by all stresses tested. These suggest that GB induces an increase of osmotic adjustments for drought tolerance, while its improvement of the antioxidative defense system including antioxidative enzymes and antioxidants may be more important for heat tolerance.

• Geomechanics and Engineering
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• 제12권1호
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• pp.53-69
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• 2017

Rock burst may cause serious casualties and property losses, and how to conduct effective monitoring and warning is the key to avoid this disaster. In this paper, we reviewed both the rock burst mechanism and the principle of using electromagnetic radiation (EMR) from coal rock to monitor and forewarn rock burst, and systematically studied EMR monitored data of 4 rock bursts of Qianqiu Coal Mine, Yima Coal Group, Co. Ltd. Results show that (1) Before rock burst occurrence, there is a breeding process for stress accumulation and energy concentration inside the coal rock mass subject to external stresses, which causes it to crack, emitting a large amount of EMR; when the EMR level reaches a certain intensity, which reveals that deformation and fracture inside the coal rock mass have become serious, rock burst may occur anytime and it's necessary to implement an early warning. (2) Monitored EMR indicators such as its intensity and pulses amount are well and positively correlated before rock bursts occurs, generally showing a rising trend for more than 5 continuous days either slowly or dramatically, and the disaster bursts generally occurs at the lower level within 48 h after reaching its peak intensity. (3) The rank of EMR signals sensitive to rock burst in a descending order is maximum EMR intensity > rate of change in EMR intensity > maximum amount of EMR pulses > rate of change in the amount of EMR pulses.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권8호
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• pp.3295-3311
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• 2020

With the wide application of hyperspectral images, it becomes more and more important to compress hyperspectral images. Conventional recursive least squares (CRLS) algorithm has great potentiality in lossless compression for hyperspectral images. The prediction accuracy of CRLS is closely related to the correlations between the reference bands and the current band, and the similarity between pixels in prediction context. According to this characteristic, we present an improved CRLS with adaptive band selection and adaptive predictor selection (CRLS-ABS-APS). Firstly, a spectral vector correlation coefficient-based k-means clustering algorithm is employed to generate clustering map. Afterwards, an adaptive band selection strategy based on inter-spectral correlation coefficient is adopted to select the reference bands for each band. Then, an adaptive predictor selection strategy based on clustering map is adopted to select the optimal CRLS predictor for each pixel. In addition, a double snake scan mode is used to further improve the similarity of prediction context, and a recursive average estimation method is used to accelerate the local average calculation. Finally, the prediction residuals are entropy encoded by arithmetic encoder. Experiments on the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) 2006 data set show that the CRLS-ABS-APS achieves average bit rates of 3.28 bpp, 5.55 bpp and 2.39 bpp on the three subsets, respectively. The results indicate that the CRLS-ABS-APS effectively improves the compression effect with lower computation complexity, and outperforms to the current state-of-the-art methods.