• Journal of Biosystems Engineering
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• 제33권4호
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• pp.260-268
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• 2008

Optical diffuse reflectance sensing has potential for rapid and reliable on-site estimation of soil properties. For good results, proper calibration to measured soil properties is required. One issue is whether it is necessary to develop calibrations using samples from the specific area or areas (e.g., field, soil series) in which the sensor will be applied, or whether a general "factory" calibration is sufficient. A further question is if specific calibration is required, how many sample points are needed. In this study, these issues were addressed using data from 42 paddy fields representing 14 distinct soil series accounting for 74% of the total Korean paddy field area. Partial least squares (PLS) regression was used to develop calibrations between soil properties and reflectance spectra. Model evaluation was based on coefficient of determination ($R^2$) root mean square error of prediction (RMSEP), and RPD, the ratio of standard deviation to RMSEP. When sample data from a soil series were included in the calibration stage (full information calibration), RPD values of prediction models were increased by 0.03 to 3.32, compared with results from calibration models not including data from the test soil series (calibration without site-specific information). Higher $R^2$ values were also obtained in most cases. Including some samples from the test soil series (hybrid calibration) generally increased RPD rapidly up to a certain number of sample points. A large portion of the potential improvement could be obtained by adding about 8 to 22 points, depending on the soil properties to be estimated, where the numbers were 10 to 18 for pH, 18-22 for EC, and 8 to 22 for total C. These results provide guidance on sampling and calibration requirements for NIR soil property estimation.

• Journal of Microbiology and Biotechnology
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• 제29권10호
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• pp.1522-1542
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• 2019

To adapt to environmental changes and to maintain cellular homeostasis, microorganisms adjust the intracellular concentrations of biochemical compounds, including metal ions; these are essential for the catalytic function of many enzymes in cells, but excessive amounts of essential metals and heavy metals cause cellular damage. Metal-responsive transcriptional regulators play pivotal roles in metal uptake, pumping out, sequestration, and oxidation or reduction to a less toxic status via regulating the expression of the detoxification-related genes. The sensory and regulatory functions of the metalloregulators have made them as attractive biological parts for synthetic biology, and the exceptional sensitivity and selectivity of metalloregulators toward metal ions have been used in heavy metal biosensors to cope with prevalent heavy metal contamination. Due to their importance, substantial efforts have been made to characterize heavy metal-responsive transcriptional regulators and to develop heavy metal-sensing biosensors. In this review, we summarize the biochemical data for the two major metalloregulator families, SmtB/ArsR and MerR, to describe their metal-binding sites, specific chelating chemistry, and conformational changes. Based on our understanding of the regulatory mechanisms, previously developed metal biosensors are examined to point out their limitations, such as high background noise and a lack of well-characterized biological parts. We discuss several strategies to improve the functionality of the metal biosensors, such as reducing the background noise and amplifying the output signal. From the perspective of making heavy metal biosensors, we suggest that the characterization of novel metalloregulators and the fabrication of exquisitely designed genetic circuits will be required.

• 농업과학연구
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• 제47권4호
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• pp.753-767
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• 2020

The commercial value of strawberries is affected by various factors such as their shape, size and color. Among them, size determined by weight is one of the main factors determining the quality grade of strawberries. In this study, image technology was developed to predict the weight of strawberries using the shape characteristics of strawberry cultivars. For realtime weight measurements of strawberries in transport, an image measurement system was developed for weight prediction with a charge coupled device (CCD) color camera and a conveyor belt. A strawberry weight prediction algorithm was developed for three cultivars, Maehyang, Sulhyang, and Ssanta, using the number of pixels in the pulp portion that measured the strawberry weight. The discrimination accuracy (R2) of the weight prediction models of the Maeyang, Sulhyang and Santa cultivars was 0.9531, 0.951 and 0.9432, respectively. The discriminative accuracy (R2) and measurement error (RMSE) of the integrated weight prediction model of the three cultivars were 0.958 and 1.454 g, respectively. These results show that the 2D imaging technology considering the shape characteristics of strawberries has the potential to predict the weight of strawberries.

• 한국응용곤충학회지
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• 제61권1호
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• pp.211-219
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• 2022

지난 10년 동안, 이중 가닥 RNA (double-stranded RNA, dsRNA)를 이용한 특정 유전자 발현 간섭(RNA interference, RNAi) 기술은 의약품 개발뿐만 아니라 작물보호 분야에 해충방제부터 익충보호까지 다양하게 그 기술이 사용되어 왔다. 그동안 학계 및 산업체에서 활발히 연구되어 온 RNAi기술을 이용한 작물 및 익충보호제는 상용화를 눈앞에 두고 있다. 미래 농업 시장에서 해충방제제와 익충보호제로써의 개발을 위한 RNAi의 기술적 응용은 상당한 잠재력을 가지고 있지만, 현장에 직접 사용되기에는 아직 여러 가지 한계점이나 극복해야 할 과제가 남아있다. 본 리뷰에서는 최근에 활발히 진행되고 있는 작물보호제 및 익충보호제(protection of crops and beneficial insects)로써의 dsRNA의 다양한 활용과 그 잠재성(potential)을 소개하고자 한다.

• 한국약용작물학회지
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• 제2권3호
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• pp.246-250
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• 1994

반하(半夏)의 엽절편(葉切片)을 배양(培養)하여 유도(誘導)한 Callus로부터 식물재분화(植物再分化)에 미치는 온도(溫度)와 광조건(光條件) 그리고 기내(器內) 괴경(塊莖) 비대(肥大)를 위한 배지내(培地內) 실소원(室素源)의 영향(影響) 등에 대하여 검토(檢討)한 결과(結果)는 다음과 같다. 1. 엽절(葉切)으로부터의 Callus 형성(形成)과 기관분화(器官分化)에는 2, 4-D 또는 NAA의 첨가(添加)가 IAA 첨가(添加)보다 좋았으며, 배양조건(培養條件)으로는 $26^{\circ}C$에서 8시간(時間)/ 일(日), 명배양(明培)하는 것이 효과적(效果的)이었다. 2. Callus로부터 식물체(植物體)를 재분화하기 위한 적정배지(適正培地)는 MS 배지(培地)에 BA $2mg/{\ell}$를 첨가(添加)하였을 때 좋았으며, 배양환경(培養環境)은 $26^{\circ}C$에서 $16{\sim}24$시간(時間)/일(日) 명배양(明培養)시키는 것이 좋았다. 3. 배지내(培地內)에 $KNO_3\;3.0g/{\ell}$처리(處理)하였을 때 식물체(植物體) 재분화배지(再分化培地) MS+BA $2mg/{\ell}$에 비하여 기내괴경(器內塊莖)의 비대(肥大)가 2.5배(培) 이상(以上)에 달하였다.

• 한국작물학회지
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• 제51권4호
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• pp.340-347
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• 2006

Soyasaponins $A_1$, DDMP-conjugated group B soyasaponins ${\alpha}g\;and\;{\beta}g$, non-DDMP counterpart soyasaponin I, II+III, and DDMP moiety were quantified in the large-, midium-, and small-seed soybean varieties. Protein contents were ranged from 38.1% to 41.8%, and oil contents were ranged from 15.5% to 18.9%, respectively. Oil contents in the large-seed varieties were significantly higher than those of medium- and small-seed varieties. Among detected soyasaponin peaks, ${\beta}g$ was a major soyasaponin in DDMP-conjugated group B soyasaponins followed by soyasaponin I, DDMP moiety and $A_1$. Soyasaponin concentration among different seed size soybean varieties. The soyasaponin concentration of mediumseed ($4014.5{\mu}g/g$) was slightly higher than those of largeseed ($3755.0{\mu}g/g$) and small-seed varieties ($3620.3{\mu}g/g$), however, the differences was statistically not significant. The composition rates of soyasaponins in the large-size seeds were 9.4% of soyasaponin $A_1$, 26.5% of DDMP-conjugated soyasaponins, 49.9% of non-DDMP counterpart soyasaponins, and 14.2% of DDMP moiety, respectively. Similar results were observed in the composition ratios of middle- and small-size seeds. Oil content and C:N ratio showed the significant positive correlations with total soyasaponin concentration, while the 100-seed weight, fiber, and ash contents showed the negative correlations with total soyasaponin but statistically not significant. It was noted that protein contents didn't have any relationship with group A, group B, DDMP moiety, and total soyasaponin. This fact suggested that protein contents are not affects the variation of soyasaponin concentration.

• 정신신체의학
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• 제12권2호
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• pp.122-134
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• 2004

연구목적 : 본 연구의 목적은 분노반응 척도를 개발하고 임상에 적용하고자 하는 데 있다. 방법: 성인 정상인 123명을 대상으로 분노반응 척도 예비설문을 시행하여 16개 문항을 추출하였다. 그 다음에 이 문항들이 포함된 설문을 정상인 258명을 대상으로 실시하였다. 상기 척도의 임상적 적용은 환자군 189명(불안장애 59명, 우울장애 72명, 신체형장애 58명)을 대상으로 하였다. 결과: 이 자료들을 요인분석한 결과 4개의 하위요인 즉 공격성반응, 짜증반응, 도피반응, 분노억압반응이 추출되었다. 상기 척도의 신뢰도는 정상인 53명에게 2주 간격으로 검사-재검사를 시행, 분석한 결과 4개 하위척도 점수와 척도 전체 점수간의 상관계수가 .53-.71로 모두 유의한 상관성을 보였다. 한편 내적 일치도는 4개 하위척도의 Cronbach's ${\alpha}$가 .62-.72, 척도 전체의 Cronbach's ${\alpha}$가 .76로 유의한 수준을 보였다. 공존 타당도의 평가는 공격성질문지 (Aggression Questionnaire) 총점, 상태-특성분노표출척도(State-Trait Anger Expression Inventory), 스트레스반응척도(Stress Response Inventory)의 분노 및 공격성 하위척도, Symptom Checklist-90-Revised (SCL-90-R)의 적대감 하위척도를 사용하였다. 환자군과 정상군 간에 척도의 전체 점수와 하위척도 점수를 비교한 결과 도피반응과 분노억압반응 하위척도에서만 각각 유의한 차이를 보였고 공격성 및 짜증반응, 척도 전체 점수에서는 유의한 차이를 보이지 않았다. 도피반응 하위척도 점수에서 우울장애군과 신체형장애군은 각각 정상군보다 유의하게 더 높았다. 결론: 이상의 결과들은 분노반응 척도가 신뢰도 및 타당도가 모두 유의한 수준의 도구이고, 특히 도피반응은 우울장애군 및 신체형장애군의 특징적인 분노반응일 가능성을 시사해 준다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권6호
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• pp.845-855
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• 2000

As high as 50% of pregnancies are known to fail and the majority of such losses occur during the peri-implantation period. For the establishment of pregnancy in mammalian species, therefore, implantation of the conceptus to the maternal endometrium must be completed successfully. Physiological events associated with implantation differ among mammals. In ruminant ungulates, an elongation of the trophohlast in early conceptus development is required before the attachment of the conceptus to the uterine endometrium. Moreover, implantation sites are restricted to each uterine caruncula where tissue remodeling, feto-maternal cell fusion and placentation take place in a coordinated manner. These unique events occur under strict conditions and are regulated by numerous factors from the uterine endometrium and trophoblast in a spatial manner. Interferon-tau (IFN-${\tau}$), a conceptus-derived anti-Iuteolytic factor, which rescues corpus luteum from its regression in ruminants, is particularly apt to play an important role as a local regulator in coordination with other factors, such as TGF-${\beta}$, Cox-2 and MMPs at the attachment and placentation sites.

• The Plant Pathology Journal
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• 제33권2호
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• pp.125-132
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• 2017

Tan spot (TS), caused by the fungus Pyrenophora tritici-repentis (Died) Drechs, is an important foliar disease of wheat and has become a threat to world wheat production since the 1970s. In this study a globally diverse pre-1940s collection of 247 wheat genotypes was evaluated against Ptr ToxA, P. tritici-repentis race 1, and stem rust to determine if; (i) acquisition of Ptr ToxA by the P. tritici-repentis from Stagonospora nodorum led to increased pathogen virulence or (ii) incorporation of TS susceptibility during development stem rust resistant cultivars led to an increase in TS epidemics globally. Most genotypes were susceptible to stem rust; however, a range of reactions to TS and Ptr ToxA were observed. Four combinations of diseasetoxin reactions were observed among the genotypes; TS susceptible-Ptr ToxA sensitive, TS susceptible-Ptr ToxA insensitive, TS resistant-Ptr ToxA insensitive, and TS resistant-Ptr ToxA toxin sensitive. A weak correlation (r = 0.14 for bread wheat and -0.082 for durum) was observed between stem rust susceptibility and TS resistance. Even though there were no reported epidemics in the pre-1940s, TS sensitive genotypes were widely grown in that period, suggesting that Ptr ToxA may not be an important factor responsible for enhanced prevalence of TS.

• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1306-1311
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• 2011

Recombinant Rhodopseudomonas palustris, harboring the carotenoid-metabolizing gene crtI (CrtIBS), and whose color changes from greenish yellow to red in response to inorganic As(III), was cultured in transparent microplate wells illuminated with a light emitting diode (LED) array. The cells were seen to grow better under near-infrared light, when compared with cells illuminated with blue or green LEDs. The absorbance ratio of 525 to 425 nm after cultivation for 24 h, which reflects red carotenoid accumulation, increased with an increase in As(III) concentrations. The detection limit of cultures illuminated with near-infrared LED was 5 ${\mu}g$/l, which was equivalent to that of cultures in test tubes illuminated with an incandescent lamp. A near-infrared LED array, in combination with a microplate, enabled the simultaneous handling of multiple cultures, including CrtIBS and a control strain, for normalization by the illumination of those with equal photon flux densities. Thus, the introduction of a near-infrared LED array to the assay is advantageous for the monitoring of arsenic in natural water samples that may contain a number of unknown factors and, therefore, need normalization of the reporter event.