• Title/Summary/Keyword: DD

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Development of Meloidogyne arenaria on Oriental Melon (Cucumis melo L.) in Relation to Degree-day Accumulation Under Greenhouse Conditions

  • Kim, Dong-Geun;Yeon, Il-Kwon
    • The Plant Pathology Journal
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    • v.17 no.3
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    • pp.159-163
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    • 2001
  • Influence of soil temperature [accumulated degree-day for the base temperature $5^{\circ}$($\textrm{DD}_5$)] on the development of Meloidogyne arenaria were studied in a winter grown oriental melon greenhouse in Seongju, Korea. Egg masses were first observed on roots at the accumulation of 565 $\textrm{DD}_5$(40 days after transplanting), suggesting that the nematode has completed the first generation in 40 days. Second-stage juveniles (J2) densities were lowest at 863 $\textrm{DD}_5$ in April, first increased at 1,334 $\textrm{DD}_5$ in May, peaked at 2,951 $\textrm{DD}_5$ in July, and decliner thereafter. Development of egg masses and J2 density in soil revealed that M. arenaria could develop in 7-8 generations in a year in the greenhouse. Degree-day monitoring, therefore, could aid to predict nematode development in soil and can be valuable tool a to develop root-knot nematode control strategies.

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Life Table Statistics of the Rice Weevil, Sitophilus oryzae(L.)(Coleoptera: Curculionidae) on the Degree-Day Scale (온일도를 시간단위로 한 쌀바구미 생명표 통계량)

  • 류문일;조기종;유춘권
    • Korean journal of applied entomology
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    • v.27 no.1
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    • pp.14-20
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    • 1988
  • 쌀바구미 생명표 통계량을 정온 조건과 실온 조건에서 산출하였다. 온일도를 단위로 하였을 때 $20^{\circ}$~ $30^{\circ}$ 범위내 정온 조건에서의 통계량은 실온 조건에서의 통계량과 유사한 차이를 보이지 않았으며 온도간의 변이는 실온에서의 간 변이와 유사하였다. 이 결과는 온일도를 시간단위로 할 때 쌀바구미의 생화사가 표준화 될 수 있음을 시사하는 것이었다. 쌀바구미는 $368pm$41.2DD에서 산란을 시작하여 $1391.0\pm$38.7DD에서 멈추는 것으로 추정되었다. 외적 자연회가졸 밀도 음가 기간과 평균세대 기간은 각각$ 0.0052\pm$0.0006/DD, $134.7\pm$15.0 DD 그리고 $715.2\pm$53.6 DD인 것으로 산출되었다.

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Optimal filter materials for protist quantification via droplet digital PCR

  • Juhee Min;Kwang Young Kim
    • ALGAE
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    • v.39 no.1
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    • pp.51-56
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    • 2024
  • The use of droplet digital polymerase chain reaction (ddPCR) has greatly improved the quantification of harmful protists, outperforming traditional methods like quantitative PCR. Notably, ddPCR provides enhanced consistency and reproducibility at it resists PCR inhibitors commonly found in environmental DNA samples. This study aimed to determine the most effective filter material for ddPCR protocols by assessing the reproducibility of species-specific gene copy numbers and filtration time across six filter types: cellulose acetate (CA), mixed cellulose ester (MCE), nylon (NY), polycarbonate (PC), polyethersulfone (PES), and polyvinylidene fluoride (PVDF). The study used two species of Chattonella marina complexes as a case study. Filtration rates were slower for NY, PC, and PVDF filters. Moreover, MCE, NY, PES, and PVDF yielded lower DNA amounts than other filters. Importantly, the CA filter exhibited the lowest variance (38-39%) and the highest determination coefficients (R2 = 0.92-0.96), indicating superior performance. These findings suggest that the CA filter is the most suitable for ddPCR quantification of marine protists, offering quick filtration and reliable reproducibility.

Effects of Dioscorea daemona Roxb. Stem Extract on the Inflammatory Responses, Antioxidant System and Lipid Levels in Vivo and the Production of Inflammatory Mediators in RAW264.7 Cells (Dioscorea daemona Roxb. (Stem) 추출물이 Rat의 염증반응 및 항산화 체계에 미치는 영향과 RAW264.7 세포주의 염증성 매개물 생성에 미치는 영향)

  • Choi Eun-Mi;Koo Sung-Ja
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.6
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    • pp.707-716
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    • 2005
  • 본 연구에서는 다양한 동물 모델을 사용하여 Dioscorea daemona Roxb. 줄기 메탄을 추출물(DD)의 항염증 활성을 측정하였으며 DD가 생체내에서 항산화 체계의 변화를 유도할 수 있는지도 살펴보았다. DD를 200mg/kg용량으로 3주간 경구투여하였을 때 동물실험모델에서 항염증 및 type IV 알레르기 억제 효과를 나타내었으며 혈청의 Catalase 활성, 지질 과산화, TG 및 HDL cholesterol 수치가 영향을 받았다. DD와 이를 클로로포름과 부탄올로 순차적으로 분획하여 얻은 fraction이 lipopolysaccharide(LPS)로 유도한 RAW264.7 대식세포주의 nitric oxide(NO), prostaglandin $E_2(PGE_2)$, tumor necrosis $factor-\alpha(TNF-\alpha)$, interleukin 6(IL6)의 생성을 억제하는지도 연구하였다. DD와 그 분획물들은 $4\~100{\mu}g/mL$ 농도에서 세포 독성을 나타내지 않고 LPS가 유도한 RAW264.7 세포주의 NO, $TNF-\alpha$, IL-6 생성을 억제하였다. LPS가 유도한 $PGE_2$ 생성은 DD의 클로로포름 분획에서 유의적으로 감소하였다(p<0.05). 따라서 Dioscorea daemona 추출물은 대식세포의 염증성 매개물의 억제를 통하여 항염증 활성을 나타내는 것으로 사료된다.

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Comparison of Diagnostic Validity between Laser Fluorescence Devices in Proximal Caries (레이저 형광 원리를 이용한 우식 진단 기기의 구치부 인접면 우식 진단 능력 비교)

  • Lee, Changkeun;Lee, Daewoo;Kim, Jaegon;Yang, Yeonmi
    • Journal of the korean academy of Pediatric Dentistry
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    • v.45 no.4
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    • pp.426-435
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    • 2018
  • The aim of this study was to evaluate the proximal caries detecting ability and identify the optimal cut-off values of two types of laser fluorescence (LF) devices; classic type (DD) and pen type (DDpen). The number of proximal surfaces participated in this study were 164 surfaces in primary dentition and 438 surfaces in permanent dentition. Each tooth surface was sequentially assessed by two types of LF devices, and bitewing radiograph. The radiographs were classified into 3 groups in primary dentition ($pR_0$, $pR_1$, $pR_2$), and 4 groups in permanent dentition ($PR_0$, $PR_1$, $PR_2$, $PR_3$) according to the depth of caries, and used as gold standard. In primary dentition, the area under the curve (AUC) values of DD were 0.851 and 0.890, and those of DDpen were 0.883 and 0.917, respectively in enamel caries and dentin caries. In permanent dentition, the AUC values of DD were 0.762 and 0.886, and those of DDpen were 0.828 and 0.958, respectively in enamel caries and dentin caries. When detecting proximal caries in posterior teeth with LF devices, DDpen is more useful than DD in both primary and permanent dentition. However, in primary dentition, DD can also be useful to detect proximal caries.

The Protective Effects of IGF-1 on Different Subpopulations of DRG Neurons with Neurotoxicity Induced by gp120 and Dideoxycytidine In Vitro

  • Lu, Lin;Dong, Haixia;Liu, Guixiang;Yuan, Bin;Li, Yizhao;Liu, Huaxiang
    • Biomolecules & Therapeutics
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    • v.22 no.6
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    • pp.532-539
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    • 2014
  • Peripheral neuropathy induced by human immunodeficiency virus (HIV) infection and antiretroviral therapy is not only difficult to distinguish in clinical practice, but also difficult to relieve the pain symptoms by analgesics because of the severity of the disease at the later stage. Hence, to explore the mechanisms of HIV-related neuropathy and find new therapeutic options are particularly important for relieving neuropathic pain symptoms of the patients. In the present study, primary cultured embryonic rat dorsal root ganglion (DRG) neurons were used to determine the neurotoxic effects of HIV-gp120 protein and/or antiretroviral drug dideoxycytidine (ddC) and the therapeutic actions of insulin-like growth factor-1 (IGF-1) on gp120- or ddC-induced neurotoxicity. DRG neurons were exposed to gp120 (500 pmol/L), ddC ($50{\mu}mol/L$), gp120 (500 pmol/L) plus ddC ($50{\mu}mol/L$), gp120 (500 pmol/L) plus IGF-1 (20 nmol/L), ddC ($50{\mu}mol/L$) plus IGF-1 (20 nmol/L), gp120 (500 pmol/L) plus ddC ($50{\mu}mol/L$) plus IGF-1 (20 nmol/L), respectively, for 72 hours. The results showed that gp120 and/or ddC caused neurotoxicity of primary cultured DRG neurons. Interestingly, the severity of neurotoxicity induced by gp120 and ddC was different in different subpopulation of DRG neurons. gp120 mainly affected large diameter DRG neurons (> $25{\mu}m$), whereas ddC mainly affected small diameter DRG neurons (${\leq}25{\mu}m$). IGF-1 could reverse the neurotoxicity induced by gp120 and/or ddC on small, but not large, DRG neurons. These data provide new insights in elucidating the pathogenesis of HIV infection- or antiretroviral therapy-related peripheral neuropathy and facilitating the development of novel treatment strategies.

A novel WD40 protein, BnSWD1, is involved in salt stress in Brassica napus

  • Lee, Sang-Hun;Lee, Jun-Hee;Paek, Kyung-Hee;Kwon, Suk-Yoon;Cho, Hye-Sun;Kim, Shin-Je;Park, Jeong-Mee
    • Plant Biotechnology Reports
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    • v.4 no.2
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    • pp.165-172
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    • 2010
  • Genes that are expressed early in specific response to high salinity conditions were isolated from rapeseed plant (Brassica napus L.) using an mRNA differential display method. Five PCR fragments (DD1.5) were isolated that were induced by, but showed different response kinetics to, 200 mM NaCl. Nucleotide sequence analysis and homology search revealed that the deduced amino sequences of three of the five cDNA fragments showed considerable similarity to those of ${\beta}$-mannosidase (DD1), tomato Pti-6 proteins (DD5), and the tobacco harpin-induced protein hin1 (DD4), respectively. In contrast, the remaining clones, DD3 and DD2, did not correspond to any substantial existing annotation. Using the DD3 fragment as a probe, we isolated a full-length cDNA clone from the cDNA library, which we termed BnSWD1 (Brassica napus salt responsive WD40 1). The predicted amino-acid sequence of BnSWD1 contains eight WD40 repeats and is conserved in all eukaryotes. Notably, the BnSWD1 gene is expressed at high levels under salt-stress conditions. Furthermore, we found that BnSWD1 was upregulated after treatment with abscisic acid, salicylic acid, and methyl jasmonate. Our study suggests that BnSWD1, which is a novel WD40 repeat-containing protein, has a function in salt-stress responses in plants, possibly via abscisic acid-dependent and/or -independent signaling pathways.

Characteristics of Annual Rings of Pinus thunbergii Grown in the Air-polluted Area by Soft X-ray Analysis (Soft X-ray분석(分析)에 의한 대기오염지역(大氣汚染地域)에서 자란 해송(Pinus thunbergii)의 연륜(年輪)의 특징(特徵))

  • Kim, Jong Kab;Kim, Jai Saing
    • Journal of Korean Society of Forest Science
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    • v.80 no.4
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    • pp.351-359
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    • 1991
  • Annual ring characteristics of pinus thunbergii grown in several air-polluted areas were investigated by soft X-ray densitometry. Ring width, maximum density and relative difference between maximum and minimum density(abbreviated to DD) were generally decreased after the beginning of operation of the factories at the vicinity of the pollution sources. Especially at the nearest areas of the industrial complex, those were distinctly decreased, and the changes, either increases or decreases, in percentage of latewood and minimum density could not be explained by the air pollution dosages. Ring width, maximum density and DD were being more apparently decreased after 5 years than those for 5 years after the beginning of operation, and also the rate of decrease was increased from after 5 years after the beginning of operation, and the rate of decrease of ring width was the highest of all. It was inferred that ring width, maximum density and DD of Pinus thunbergii could be used as indicators to detect the growth damage by air pollution.

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Performance of CEFSK Systems in Nonlinear Channel Environments (비선형 채널 환경에서 CEFSK 시스템의 성능)

  • Lee, Kee-Hoon;Choi, Byeong-Woo;Shin, Kwan-Ho;Seo, Jong-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.1
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    • pp.79-87
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    • 2013
  • A new modulation technique - correlative encoded FSK (CEFSK) - for use in power and bandwidth limited digital communication system is proposed. CEFSK is free of ISI and generates output signals which have a smooth and continuous phase transition and a reduced envelope fluctuation by keeping correlation between amplitude and phases of two subsequent symbols. In comparison to conventional one-bit differential detected (1DD) GFSK, the performance of the 1DD-CEFSK in a non-linearly amplified (NLA) channel impaired by additive white Gaussian noise (AWGN), ISI and IM, is analyzed via computer simulation. The simulation result shows that, in an NLA single-channel, 1DD-CEFSK provides a signal-to-noise ratio (SNR) advantage of up to 1.2dB and 0.8dB at BER of $1{\times}10^{-4}$ when input back-off (IBO) of HPA is -1.0dB and -3.0dB, respectively. For the same channel environment with multi-channel, 1DD-CEFSK outperforms 1DD-GFSK by 1.1dB in SNR, regardless of the value of IBO.

DC-DC Boost Converter for Thermoelectric Energy Harvesting (열전 에너지 하베스팅을 위한 저전압 DC-DC 부스트 변환기)

  • Kim, Myeong-Kyu;Kim, Han-Na;Bang, Jun-Jeong;Hwang, In-Ho;Yu, Chong-Gun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.247-250
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    • 2012
  • This paper describes a DC-DC Boost converter for Thermoelectric Energy Harvesting. The designed converter boosts the $V_{DD}$ through a start-up block from a low output voltage of thermoelectric devices and the boosted $V_{DD}$ is used to operate the internal block circuits. When $V_{DD}$ reaches a predefined value, a detector circuit makes the start-up block turn off for minimizing current consumption. The final boosted $V_{OUT}$ is achieved by alternately operating the DC-DC converter for $V_{DD}$ and the other converter for final output $V_{OUT}$ according to the comparator output. Simulation results shows that the designed converter outputs 2.8V from an input voltage of 200mV. The area of the chip designed using a 0.35um CMOS process is $1.52mm{\times}0.95mm$ including pads.

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