• 제목/요약/키워드: AoA

검색결과 486건 처리시간 0.026초

Taxonomy of Yellow koji mold (Aspergillus flavus/oryzae) in Korea

  • Hong, Seung-Beom;Lee, Mina;Kim, Dae-Ho;Chung, Soo-Hyun;Samson, Robert A.
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2014년도 춘계학술대회 및 임시총회
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    • pp.25-25
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    • 2014
  • Koji molds are comprised of yellow, black and white. Black and white koji molds were recently re-visited by this author and it is concluded that they consists of Aspergillus luchuesnsis, A. niger and A. tubingensis, and the most important species for alcoholic beverage production is A. luchuensis. In the case of yellow koji mold, it is comprised of Aspergillus oryzae, A. sojae and A. tamari. In the case of A. sojae, the species is scarcely isolated from nature and rarely used for industry in Korea. Aspergillus tamari is often isolated from traditional Korean Meju, a fermented soybean product, and the classification of the species is clear. However, in the case of A. oryzae, differentiation between A. oryzae and A. flavus is still in controversy. In this study, we collected 415 strains of Aspergillus flavus/oryzae complex from air, rice straw, soybean, corn, peanut, arable soil and Meju in Korea and we examined the aflatoxin producing capacity of the strains. The norB-cypA, omtA and aflR genes in the aflatoxin biosynthesis gene cluster were analyzed. We found that 367 strains (88.4%) belonged to non-aflatoxigenic group (Type I of norB-cypA, IB-L-B-, IC-AO, or IA-L-B- of omtA, and AO type of aflR), and only 48 strains (11.6%) belonged to aflatoxin-producible group (Type II of norB-cypA, IC-L-B+/B- or IC-L-B+ of omtA, and AF type of aflR). In the case of A. flavus/oryzae strains from Meju, almost strains (178/192, 92.7%) belonged to non-aflatoxigenic group and only 14 strains (7.3 %) belonged to aflatoxin-producible group. It is proposed in this study that non-aflatoxigenic strain from Meju is classified as A. oryzae, considering that Meju is food material.

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Alkyl and Alkenyl Substituent Effects on Nonbonded Interactions of Hexatriene

  • Lee, Ik-Choon;Rhyu, Keun-Bae;Lee, Bon-Su
    • Bulletin of the Korean Chemical Society
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    • 제2권1호
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    • pp.12-16
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    • 1981
  • Alkyl and alkenyl substituent effects on nonbonded interactions of hexatriene were examined using CNDO/2 method. The results showed that: (1) rapid rate of thermal electrocyclization of 3-vinyl hexa-1, 3, 5-triene is due to increased overlap population between atom pair reacting resulting from strong electron repelling interaction of vinly group on the triene moiety; (2) stability of a conformer is determined by additive effect of composite ${\pi}$ structures; (3) a substituent on positions 2 and 3 increases the HOMO AO coefficient of sites 1 and 4 considerably and activates interactions with these sites.

독어음의 음성학적 고찰(2) - 현대독어의 복모음에 관하여 - (A Phonetic Study og German (2))

  • 윤종선
    • 대한음성학회지:말소리
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    • 제19_20호
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    • pp.33-42
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    • 1990
  • Those who are interested in the German diphthongs wil1 find that they are classified into three kinds of forms in accordance with their gliding directions: closing, centring and rising. The German [aI], for example, which derives its origin from [i:] of the riddle high German. Is regarded as a distinctive feature that distinguishes the new high German from the middle high German. The diphthong [aI] is cal led fall ing one, because the sonority of the sound undergoes a diminution as the articulation proceeds. The end part of the diphthong [aI] is less sonorous than the beginning part. In most of the German diphthongs the diminution of prominence is caused by the fact that the end part is inherently less sonorous than the beginning. This applies to the other c los Ing and centring diphthongs. This way of diminution of sonority exerts influence on methods of constructing systems of phonetic notation. The above mentioned less sonorous end part of diphthong [I] shows that it differs from some analogous sound in another context. It is useful to demonstrate the occurrence of particular allophones by introducing special symbols to denote them (here: at→ae). Forms of transcription embodying extra symbol s are cal led narrow. But since strict adherence to the principle 'one sound one symbol' would involve the introduction of a large number of symbols, this would render phonetic transcriptions cumbrous and difficult to read. A broad style of transcription provides 'one symbol for each phoneme' of the language that is transcribed. Phonemic transcriptions are simple and unambiguous to everyone who knows the principles governing the use of allophones in the language transcribed. Among those German ways of transcriptions of diphthongs ( a?, a?, ??: ae, ao, ?ø; ae, ao, ?ø) the phonemic (broad) transcription is general Iy to be recommended, for Instance, in teaching the pronunciation of a foreign language, since it combines accuracy with the greatest measure of simplicity (Some passages and terms from Daniel Jones) .

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Extracts of Aster species Inhibit Invasive Phenotype and Motility of H-ras MCF10A Human Breast Epithelial Cells Possibly via Downregulation of MMP-2 and MMP-9

  • Ahn, Seong-Min;Lee, Kang-Ro;Moon, A-Ree
    • Biomolecules & Therapeutics
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    • 제10권4호
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    • pp.240-245
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    • 2002
  • Cancer metastasis represents the most important cause of cancer death and antitumor agents that may inhibit this process have been extensively pursued. Invasion and metastasis of malignantly transformed cells involve degradation of the extracellular matrix (ECM) components by matrix metalloproteinases (MMP), especially MMP-2 and -9. We previously showed that H-ras-induced invasive phenotype may involve MMP-2, rather than MMP-9, in MCF10A cells. In the present study, we investigated the chemopreventive effect of Aster, a widely used culinary vegetable in Korea. We screened twelve extracts from three Aster species (Aster scaber, Aster oharai and Aster glehni) for the inhibitory effect on MMP activities of H-ras MCF10A human breast epithelial cells. All of the extracts tested in this study efficiently inhibited the gelatinolytic activities of MMP-2 and MMP-9. A more prominent inhibition was observed in MMP-2 activity compared to MMP-9. Out of twelve extracts, eight extracts showed>90% inhibition of MMP-2 activity in H-ras MCF10A cells while only one extract showed>90% inhibition of MMP-9 activity. We selected three extracts (AO-3, AG-3 and AS-EA) for further studies since they exerted a marked inhibition in the ratio of MMP-2 to MMP-9. Treatment with AO-3, AG-3 and AS-EA in H-ras MCF10A cells caused a significant inhibition of invasive phenotype and migration, proving a chemopreventive potential of these extracts. Taken together, our results demonstrate that extracts of Aster effectively inhibit invasion and migration of highly malignant human breast cells, possibly via downregulation of MMP-2 and MMP-9.

골수정을 이용한 대퇴골 전자간 골절의 새로운 치료 경향 (New Approach in the Treatment of Intertrochanteric Fracture Using a Cephalomedullary Nail)

  • 김준영;최기홍;양규현
    • 대한정형외과학회지
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    • 제55권3호
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    • pp.193-199
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    • 2020
  • 골수강 내 금속정(골수정)은 1988년부터 대퇴골 전자간 골절을 치료하는 데 사용되어 왔다. 골수정은 활강고나사와 같은 골수강 외 고정 장치에 비하여 기계적 이점이 있으나 대퇴 전자간 골절 Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) 31-A1 및 31-A2 골절 치료에 활강고나사보다 유리한 고정 기구인지에 대해서는 논란이 계속되고 있다. 지난 30년 동안 여러 시행 착오가 극복되었고 새로운 유형의 대퇴 골수정이 개발되어 임상에서 사용되고 있다. 새로 개발된 골수정은 삽입 과정이 쉬워지고 지연나사를 사용한 대퇴 골두의 고정 능력이 향상되어 왔다. 그러나 고정 실패율은 여전히 정형외과 의사의 수술 술기에 달려 있다고 할 수 있다. 이 종설에서 우리는 골수정을 이용하여 대퇴 전자간 골절을 치료하는 동안 내측 지지대 복원의 중요성에 대해 초점을 맞추고 그 기본 원칙에 대하여 논의해 보고자 한다.

Degradation of toxic azo dye (AO7) using Fenton's process

  • Sharma, Ashish;Verma, Manisha;Haritash, A.K.
    • Advances in environmental research
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    • 제5권3호
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    • pp.189-200
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    • 2016
  • This study aimed at advanced oxidation of hetero tri-functional reactive dye Acid orange 7 using photo-Fenton conditions in a lab-scale experiment. Decolourisation of Acid Orange 7 dye by Fenton's process was dependent on concentration of Hydrogen peroxide, Ferrous sulphate, pH, and contact time. A $2^3$ factorial design was used to evaluate the effects of these key factors: pH, Fe(II), and $H_2O_2$ concentration, for a dye concentration of 50 mg/L with COD of 340 mg/L at pH 3.0. The response function was removal of colour under optimised conditions; pH 3.0, [Fe(II)] 40.83 mg/L, [$H_2O_2$] 4.97 mmol/L; 13.6 min. of treatment resulting in 100% colour removal. The final COD of treated wastewater was nil suggesting that AOP is a potentially useful process of color removal and dye degradation/mineralisation of effluent having AO7. Minimum contact time for complete decolourisation was at 5 mmol/l $H_2O_2$ concentration. Increase in $FeSO_4$ (mg/l) concentration resulted in decrease of time for complete decolourisation. Box-Behnken Design was used to optimize the process variables. Maximum and minimum levels of pH (3-5), $H_2O_2$ (4-6 mmol/l), $FeSO_4$ (30-46 mg/l) and contact time (5-15 minutes) were used. The statistical analysis revealed a value of 0.88 for coefficient of regression ($R^2$) indicating a good fit of model. Calculated F-value was found higher than the tabulated value confirming to significance of the model. Based on student's t-test, Ferrous sulphate, pH, and contact time have a positive effect on the percent decolourisation of Acid Orange 7.

유도초음파를 이용한 박판에서의 결함의 검출에 관한 연구 (Detection of Defects in a Thin Steel Plate Using Ultrasonic Guided Wave)

  • 정희돈;신현재
    • 비파괴검사학회지
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    • 제18권6호
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    • pp.445-454
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    • 1998
  • 본 연구는 박판 용접부 결함 검출 기법의 확립을 위해서 실시된 기초 연구로서, 전기강판 소재의 모재에 인위적인 결함을 작성하고, 이론 및 시험적 결과를 이용하여 결함을 검출하기 위한 최적의 조건과 임계 검출 결함 크기를 조사한 것이다. 이를 위해서 소재의 dispersion curve를 구하고, 두께 2.4mm의 박판에 대해서 tone burst방식에 의한 초음파 탐상을 실시하였다. 실험적 검토를 행한 결과 840kHz의 가진 주파수와 30도 그리고 85도의 입사각이 최적의 탐상 조건임을 알았다. 한편, 초음파의 속도와 dispersion커브를 비교 검토하여 본 바, 30도의 입사각에서 발생하여 전파하는 초음파는 symmetic mode이고 85도의 입사각에서는 antisymmetric mode의 파가 전파하고 있었다. 결함의 위치와 형상에 따라 반사파의 특성이 다르게 나타나고 있었으며, 특히 표면 결함의 경우에는 antisymmetric 모드의 초음파가 symmetric 모드 보다 높은 반사파 에너지를 나타내고 있었다. 또한 이러한 초음파 모드의 종류와 결함 검출과의 관계에 대해서는 유도파의 구조에 의해서 설명이 가능했다.

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Refracture after locking compression plate removal in displaced midshaft clavicle fractures after bony union: a retrospective study

  • Park, Ho-Youn;Kim, Seok-Jung;Sur, Yoo-Joon;Jung, Jae-Woong;Kong, Chae-Gwan
    • Clinics in Shoulder and Elbow
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    • 제24권2호
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    • pp.72-79
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    • 2021
  • Background: A midshaft clavicle fracture is a common fracture that typically responds well to open reduction and internal fixation (ORIF). However, refracture can occur after implant removal (IR). This study aimed to analyze the rate of refracture and related factors after removal of the locking compression plate (LCP) for displaced midshaft clavicle fractures. Methods: We retrospectively reviewed the medical records of 201 patients who had undergone ORIF with LCP for midshaft clavicle fractures after IR after bony union from January 2011 to May 2018 at our institute. We evaluated basic demographic characteristics and radiographic parameters. All patients were treated with an LCP for primary fracture. The patients were divided into two groups: a refracture group that experienced a second fracture within 1 year after IR and a no-fracture group. Results: There were four cases (1.99%) of refracture; three were treated conservatively, while one was treated surgically. All patients achieved bony union. The average interval between refracture and IR was 64 days (range, 6-210 days). There was a significant difference in classification of fractures (AO Foundation/Orthopaedic Trauma Association [AO/OTA] classification) between the two groups. However, other patient demographics and radiographic measurements between refracture and IR, such as bone diameter, showed no significant difference between the two groups. Conclusions: This study showed that one in 50 patients suffered from refracture after removal of the LCP. Thus, if patients desire IR, the surgeon should explain that there is a relatively higher possibility of refracture for cases with simple or segmental fractures than for other types of fracture.

부분적으로 관측가능하고 비결정적인 계획문제를 풀기 위한 휴리스틱 탐색 알고리즘 (A Heuristic Search Algorithm for Solving Partially-Observable, Non-Deterministic Planning Problems)

  • 김현식;박찬영;김인철
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제15권10호
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    • pp.786-790
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    • 2009
  • 본 논문에서는 불완전한 인식과 비결정적 동작을 함께 포함한 조건부 계획문제를 풀기 위한 새로운 휴리스틱 탐색 알고리즘 HSCP를 소개한다. HSCP 탐색 알고리즘은 하나의 완전한 해 그래프가 구해질 때까지 AND-OR 탐색시도를 반복한다. HSCP 알고리즘의 AND-OR 탐색시도는, 기존의 휴리스틱 AND-OR 탐색 알고리즘들인 $AO^*$$LAO^*$와는 달리, 오직 하나의 후보 해 그래프를 확장하는데 집중한다. 또한, 실시간 동적 프로그래밍 알고리즘들인 RTDP와 LRTDP와는 달리, 모든 상태들의 가치 평가치가 수렴할 때까지 미루지 않고 바로 해를 구한다. 따라서 HSCP 탐색 알고리즘은 양질의 조건부 계획을 매우 효율적으로 구해줄 수 있다는 장점이 있다.

항공기의 실속 회복을 위한 자동 회복 장치 설계 및 검증에 관한 연구 (A Study on the Design and Validation of Automatic Pitch Rocker for the Aircraft Deep Stall Recovery)

  • 한성호;황병문;이영호;이동규;안성준;김종섭
    • 제어로봇시스템학회논문지
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    • 제13권1호
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    • pp.6-14
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    • 2007
  • Modem version of supersonic jet fighter aircraft must have been guaranteed appropriate controllability and stability in HAoA(High Angle of Attack). Limit value of aircraft entering into the departure in HAoA is related to aircraft configuration design. But, the control law such as AoA and yaw-rate limiter is implemented in digital Fly-By-Wire flight control system of supersonic jet fighter to guarantee the aircraft's safety in HAoA. The HAoA flight control law have two parts, one is control law of departure prevention and the other is control law of departure recovery support. The control laws of departure prevention for advanced jet trainer consist AoA limiter, roll command limiter and rudder fader. The control laws of departure recovery support are consist yaw-rate limiter and MPO(Manual Pitch Override) mode. The guideline of pitch rocking using MPO mode is simple, but operating skill of pitch rocking is very difficult by the pilot with inexperience of departure situation. This paper addresses the design and validation of APR(Automatic Pitch Rocker) control law instead of MPO in order to automatic recovery without manual pitch rocking by the pilot. And, recovery characteristic with APR verifies by the nonlinear analysis and pilot evaluation.