• 제목/요약/키워드: Low intensity spots

검색결과 13건 처리시간 0.042초

Alachlor에 의한 귀리 근단(根端) 분열조직(分裂組織)의 단백질(蛋白質) Pattern의 변이(變異) (Changes in the Polypeptide Patterns of Oat Root Tips Exposed to Alachlor)

  • 권성환;박기인;김재철
    • 한국잡초학회지
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    • 제12권4호
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    • pp.368-373
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    • 1992
  • 귀리에 alachlor를 처리(處理)할 때 변화(變化)되는 단백질(蛋白質)을 분석(分析)한 결과요약(結果要約)하면 다음과 같다. Alachlor 처리시(處理時) 단백질(蛋白質) 합성(合成)은 $1{\times}10^{-4}$M에서 5.8%, $1{\times}10^{-3}$M에서는 86.5% 억제(抑制)되는 현상(現象)을 보였지만 $1{\times}10^{-5}$M 이하(以下)의 농도(濃度)에서는 증가(增加)되는 현상(現象)을 보였다. 귀리의 근단분열조직(根端分裂組織)에서 추출(抽出)된 단백질(蛋白質)은 100 kd 이하(以下)의 polypeptide로 구성(構成)되어 있으며, alachlor 처리시(處理時) 47kd 이상(以上)의 고분자(高分子) 단백질(蛋白質)들은 억제(抑制)되었지만 23kd 이하(以下)의 저분자(低分子) 단백질(蛋白質)들은 오히려 증가(增加)되는 현상(現象)을 보였다. 이차원적(二次元的) 전기영동(電氣泳動) 결과(結果) alachlor 처리시(處理時) 83kd의 1, 2 spot, 70kd의 3, 4 spot, 47.5kd의 5, 6 spot의 polypeptide가 억제(抑制)된 반면(反面), 20kd의 7 spot, 16kd 의 8, 9, 10 spot는 증가(增加)되는 현상(現象)을 보였다. 또한 귀리 근단(根端) 분열조직(分裂組織)은 산성(酸性) 단백질(蛋白質)로서, 주(主)로 중성(中性) 부위(部位)에 큰 polypeptide spots들이 존재(存在)하고 있으며, 작은 spots을은 산성(酸性)쪽에 분리(分離)되어 나타났다.

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Major environmental factors and traits of invasive alien plants determining their spatial distribution

  • Oh, Minwoo;Heo, Yoonjeong;Lee, Eun Ju;Lee, Hyohyemi
    • Journal of Ecology and Environment
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    • 제45권4호
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    • pp.277-286
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    • 2021
  • Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

단감의 저온저장방법(低溫貯藏方法) 개발(開發)에 관(關)한 연구(硏究) (Development of Low-Temperature Storage Method of Sweet Persimmons)

  • 정종훈;서상룡
    • Journal of Biosystems Engineering
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    • 제19권3호
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    • pp.232-246
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    • 1994
  • This study was conducted to develop the long-tenn storage method to minimize the black spot occurred on the surface of persimmons stored in the films at low temperature. The storage experiments were done with different films and persimmon varieties at $0^{\circ}C$ storage condition for 5 months, and then the physical and chemical characteristics of persimmons were tested monthly. The results were as follows : 1. The film 160 made from zeolites showed highest performance in well storings sweet persimmons for 5 months, compared with other films by eyesight. The initial moisture condensation inside the films seemed to cause the black spots on persimmons, and the effect of the film holes was never significant to prevent the black spots. 2. The sugar content was ranged from $14^{\circ}Brix$ to $15^{\circ}Brix$ regardless of film types and persimmom varieties, and it changed little for storage of 5 months. 3. The decrease rate of persimmom weight in the film 160 and 180 was 0.3% for storage of 5 months, while those in other films reached to 2%. The decrease rate of persimmon weight was least in the film 160 and 180. 4. The hardness of Fuyu least decreased in the films 160 and 380. It was changed from 36 kg/cnf to 8-27 $kg/cm^2$, and that of Charyang was from 31 $kg/cm^2$ to 8-10 $kg/cm^2$ for storage of 5 months. The hardness of Charyang rapidly decreased as storage period increased. 5. The average rate of black spot(defect rate) of Fuyu measured by a computer image processing system was least in the film 160 by 0.5%, but those in other films was ranged from about 5% to 20% for storage of 5 months. The rate of black spot of Charyang was less than that of Fuyu among most of films. 6. The intensity, hue, and saturation in persimmon color changed according to storage period. Especially, the intensity of persimmon colors decreased as storage period increased, but it was least in the film 160. 7. An integrated long-term storage method of sweet persimmons was suggested in the basis of the experiments and literature reviews.

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잡음에 강건한 주목 연산자를 이용한 효과적인 BLU 얼룩 검사 (An Efficient BLU Inspection Using Noise-Tolerant Context-free Attention Operator)

  • 박창준;최흥문
    • 대한전자공학회논문지SP
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    • 제38권6호
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    • pp.640-647
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    • 2001
  • 본 논문에서는 BLU(back light unit) 검사에 적합하도록 잡음에 강건한 일반화 대칭 변환을 주목 연산자로 제안하여 적용함으로써 형태와 크기 및 명도가 다양한 BLU 얼룩들을 효과적으로 검출하였다. 제안한 주목 연산자는 두 화소 명도변화의 크기와 대칭성뿐만 아니라 그 방사(radial)방향의 수렴 및 발산 극성도 반영시켜 잡음이나 불규칙한 배경영상의 양극성 대칭도 누적을 상쇄시킴으로써 명도분포가 일정치 않고 복잡한 무늬의 배경을 갖는 BLU 특유의 검사영상으로부터 얼룩만을 효과적으로 검출할 수 있도록 하였다. CCD 카메라로 입력된 고해상도의 BLU 검사영상에 대해 실험하여 BLU 얼룩 검사에 효과적으로 활용할 수 있음을 확인하였다.

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Characteristics of Focused Ultrasound Mediated Blood-Brain Barrier Opening in Magnetic Resonance Images

  • Kyung Won Chang;Seung Woo Hong;Won Seok Chang;Hyun Ho Jung;Jin Woo Chang
    • Journal of Korean Neurosurgical Society
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    • 제66권2호
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    • pp.172-182
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    • 2023
  • Objective : The blood-brain barrier (BBB) is an obstacle for molecules to pass through from blood to the brain. Focused ultrasound is a new method which temporarily opens the BBB, which makes pharmaceutical delivery or removal of neurodegenerative proteins possible. This study was demonstrated to review our BBB opening procedure with magnetic resonance guided images and find specific patterns in the BBB opening. Methods : In this study, we reviewed the procedures and results of two clinical studies on BBB opening using focused ultrasound regarding its safety and clinical efficacy. Magnetic resonance images were also reviewed to discover any specific findings. Results : Two clinical trials showed clinical benefits. All clinical trials demonstrated safe BBB opening, with no specific side effects. Magnetic resonance imaging showed temporary T1 contrast enhancement in the sonication area, verifying the BBB opening. Several low-signal intensity spots were observed in the T2 susceptibility-weighted angiography images, which were also reversible and temporary. Although these spots can be considered as microbleeding, evidence suggests these are not ordinary microbleeding but an indicator for adequate BBB opening. Conclusion : Magnetic resonance images proved safe and efficient BBB opening in humans, using focused ultrasound.

Study on the monthly changes of Perkinsus infection in Komsoe Bay, Chullabukdo, Korea

  • Park, Kwang-Sik;Park, Kyung-Il
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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    • pp.505-505
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    • 2000
  • Perkinsus sp. has been identified as responsible organism for the decrease in Manil clam production along the west and south coast of Korea. Monthly investigation on infection intensity and pathology of Perkinsus infected Manila clam population was carried out in Komsoe Bay located in the west coast during February and December 1999. About one hundred clams were collected each month for the analysis. Infected clams were incubated in fluid thioglycollate media over a week, stained with iodine solution, digested with 2M NaOH and the number of Perkinsus present in an individual recorded. Histological slides were also prepared from infected clams and their pathologic symptoms were examined using a microscope. Trophozoites of Perkinsus sp. were dominantly distributed on gills and epithelia of digestive glands however a few numbers could be detected at siphons and foot tissues. Heavily infected clams often exhibited white spots on mantle and foot tissues due to the inflammatory reaction of the hemocytes, forming nodules. Trophozoites were also found along the connective tissues of follicles during spawning season indicating that Perkinsus sp. may disturb reproduction of the clam. Total number of Perkinsus sp. in an individual clam varied from none to 9, 550, 000 with a monthly mean of 279, 663 to 2, 198, 558 during the course of study. The number of Perkinsus sp. in the clam was found to lowest durin July and August when unusually low salinity was recorded in this area due to the heavy rain. Highest monthly infection intensity in terms of total number of Perkinsus sp. i clam was observed in February, when water temperature recorded as lowest during the study. Small size of clams with shell length of ten mm or less were not infected with Perkinsus sp. It was concluded that Perkinsus infection in Manila clam is in pa controlled by changes in salinity and clam growth; low salinity environment minimize infection intensity while tile clams get more Perkinsus as they grow.

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Determining a Detectable Threshold of Signal Intensity in cDNA Microarray Based on Accumulated Distribution

  • Gao, Xia;Fu, Xuping;Li, Tao;Zi, Jian;Luo, Yao;Wei, Qing;Zeng, Erliang;Xie, Yi;Li, Yao;Mao, Yumin
    • BMB Reports
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    • 제36권6호
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    • pp.558-564
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    • 2003
  • In microarray data mining, one of the key problems is how to handle weak signals. Based on a bent piecewise linear accumulated distribution generally found in the microarray data, a new detectable threshold finding method is proposed to filter genes with unreliable information in this paper. More reliable and reproducible data is produced for the subsequent data mining.

Two-Stage Logistic Regression for Cancer Classi cation and Prediction from Copy-Numbe Changes in cDNA Microarray-Based Comparative Genomic Hybridization

  • Kim, Mi-Jung
    • 응용통계연구
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    • 제24권5호
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    • pp.847-859
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    • 2011
  • cDNA microarray-based comparative genomic hybridization(CGH) data includes low-intensity spots and thus a statistical strategy is needed to detect subtle differences between different cancer classes. In this study, genes displaying a high frequency of alteration in one of the different classes were selected among the pre-selected genes that show relatively large variations between genes compared to total variations. Utilizing copy-number changes of the selected genes, this study suggests a statistical approach to predict patients' classes with increased performance by pre-classifying patients with similar genetic alteration scores. Two-stage logistic regression model(TLRM) was suggested to pre-classify homogeneous patients and predict patients' classes for cancer prediction; a decision tree(DT) was combined with logistic regression on the set of informative genes. TLRM was constructed in cDNA microarray-based CGH data from the Cancer Metastasis Research Center(CMRC) at Yonsei University; it predicted the patients' clinical diagnoses with perfect matches (except for one patient among the high-risk and low-risk classified patients where the performance of predictions is critical due to the high sensitivity and specificity requirements for clinical treatments. Accuracy validated by leave-one-out cross-validation(LOOCV) was 83.3% while other classification methods of CART and DT performed as comparisons showed worse performances than TLRM.

채층 활동이 강한 별들의 분광선 (SPECTRA OF CHROMOSPHERICALLY ACTIVE STARS)

  • 강영운;김호일;이우백;오규동
    • 천문학논총
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    • 제15권spc1호
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    • pp.93-102
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    • 2000
  • We have reviewed the magnetic activity in close binaries. Solar like magnetic activity indicators such as photometric spots, chromo spheric emission, coronal X-ray and radio emission, and flare activity are commonplace in many cool stars with convective envelopes. Using the UV spectra we confirmed the strength of stellar activity increases with more rapid rotation and later spectral types which corresponds to the increasing depth of the star's convective envelope. Apart from very young stellar objects such as T Tauri stars, the stars with the highest levels of activity are close binary systems composed of cool stars, i.e., the chromospherically active binaries such as RS CVn, BY Dra, W UMa and related systems. The IUE low and high dispersion spectra of V711 Tau, VW Cep and SW Lac are used for ultraviolet photometry and for a variation study of chromospheric activity. Evidence of chromospherically activity is indicated by the intensity variation of the Mg II emission line with orbital phase.

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무인 비행체를 이용한 위치 추적 시스템 (Location Tracking Method using UAV)

  • 염성관;민준홍;신광성
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2021년도 춘계학술대회
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    • pp.514-515
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    • 2021
  • 본 논문은 LoRa 통신 환경에서 UAV를 이용하여 표적을 찾는 방법을 제시한다. 제안 된 방법은 사각 지대없이 목표 신호를 찾을 수 있도록 UAV 비행 경로를 제안한다. 비행 경로는 신호 강도의 변화를 사용하여 비행 중 전송 된 신호의 강도를 사용하여 변경되었습니다. 제안 된 방법을 시뮬레이션으로 검증하여 3 회 비행의 효율성은 높지만 목표 추적에 시간이 오래 걸리는 것을 확인했다. 목표를 찾는데 걸리는 시간을 줄이고 시간이 중요한 요소 일 때 효율성을 높이려면 3 대의 UAV를 비행하는 것이 가장 좋다. LoRa 통신은 생산 비용을 낮추고 저비용으로 시스템 구축을 가능하다.

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