• 제목/요약/키워드: $K_0$ condition

검색결과 10,468건 처리시간 0.047초

Physiological responses involved in reactive oxygen species (ROS) of rice plant under alone or multi artificial stress conditions

  • Kim, Yoonha;Waqas, Muhammad;Khan, Abdul Latif;Mun, Bong-Gyu;Yun, Byung-Wook;Lee, In-Jung
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.203-203
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    • 2017
  • The Earth's climate is rapidly changing because of increasing carbon dioxide content in atmosphere so, climate prediction models anticipate that earth surface temperature will rise by 3 to $5^{\circ}C$ in next 50 to 100 years. Therefore, frequency of un-expected weather events such as drought, salinity, low or high temperature and flooding etc. will be increasing worldwide. Furthermore, increased atmosphere temperature can influence pests and pathogens spread as well. Therefore, to protect enormous grain loss from unexpected weather conditions, studies related with combine stress conditions like abiotic plus biotic stress condition are really required. Thus, our research focused on physiological responses under combined abiotic and biotic stress condition in rice plant. To induce uniform stress condition, we used NaCl (100 mM) and salicylic acid (0.5 and 1.0 mM SA) as each stress a stimulator. Each artificial abiotic and biotic stress inducer was applied to hydroponically grown rice seedlings alone or together for four day. The data were collected in a time-dependent manner [1, 2, 3 and 4 day(s) after treatment (DAT)] and were matched with our anticipation that shoot length and shoot fresh weight was decreased in solo and combined abiotic and biotic stress condition. The lipid peroxidation content was significantly increased ($1.5{\pm}0.2$ to $2.7{\pm}0.1mg$ mg of $MDA\;g^{-1}FW$) in the first two days in both stress exposed plants, and showed the opposite trend ($0.5{\pm}0.01$ to $0.1{\pm}0.001mg$ of $MDA\;g^{-1}FW$) in last two days under multi stress condition. Superoxide dismutase (SOD) activity did not showed difference in only biotic stress condition (alone 0.5 and 1.0 mM SA) as compared to control however, it was significantly increased in multi stress condition or solo abiotic stress condition whereas, catalase (CAT), and ascorbate peroxidase (APX) activities were significantly decreased in solo biotic and combined abiotic and biotic condition. In particular, both enzymes activities were more decreased in multi stress condition as compared to solo biotic stress condition. The results for relative mRNA expression level of CAT and APX enzymes were in agreement with results of spectrophotometric values. Correlation value between each stress condition and phenotypic data showed that biotic stress condition showed high correlation with activity of CAT and APX whilst, abiotic stress condition revealed significant correlation with SOD activity.

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풍화토의 $K_0$ 조건하 거동에 대한 구성모델 (A Constitutive Model on the Behavior under $K_0$ Condition for Weathered Soils.)

  • 오세붕;김욱;정강복
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.169-174
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    • 2003
  • Undrained triaxial tests were performed under $K_{0}$ condition for a weathered soil, which includes local measurement using LVDT. An anisotropic hardening model based on effective stress concept could predict the stress-strain relationship under $K_{0}$ condition reasonably, which makes it possible to analyze geotechnical problems for the weathered soil.

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Comparing Bioavailability of Cadmium and Arsenic in Agricultural Soil Under Varied pH Condition

  • Oh, Se Jin;Kim, Sung Chul;Ok, Yong Sik;Oh, Seung Min;Lee, Bup Yeol;Lee, Sang Hwan;Yang, Jae E.
    • 한국토양비료학회지
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    • 제48권1호
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    • pp.57-63
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    • 2015
  • Bioavailability of cadmium (Cd) and arsenic (As) can be different depending on soil pH. For this reason, main purpose of this research was to compare bioavailability of Cd and As in agricultural field under varied soil pH and different extractants. Bioavailable fraction of Cd and As in soil was extracted with $CaCl_2$, $NaNO_3$, DTPA, EDTA, and low molecular weight organic acids (LMWOAs). Soil samples and cultivated crops were collected at the range of soil pH 4.5-8.5 and correlation analysis was conducted between bioavailable fraction of Cd and As in soil and total concentration of Cd and As in crops. Results showed that concentration of Cd and As in acidic soil was ranged $0.002-0.462mg\;kg^{-1}$ and $0.041-4.903mg\;kg^{-1}$ respectively. In alkaline condition, concentration of Cd and As were ranged $0.006-0.351mg\;kg^{-1}$ and $0.039-2.807mg\;kg^{-1}$ respectively. Comparing bioavailable fraction of Cd and As in acidic and alkaline soil condition, higher concentration was measured in acidic condition. Similarly, higher average concentration of Cd and Asin crops was observed in acidic condition (0.398 and $0.751mg\;kg^{-1}$ respectively) than alkaline condition (0.248 and $0.264mg\;kg^{-1}$). Among different extractants, LMWOAs method showed higher correlation ($r^2=0.545$) for Cd in acidic condition indicating that LMWOAs method could be applied for evaluating bioavailability of Cd in acidic soil. However, no high correlation was observed for As in both acidic and alkaline condition. Overall, bioavailable fraction of Cd and As can be higher in acidic condition of soil than alkaline condition resulting higher uptake of Cd and As from soil to crops. Therefore, efficient best management practice (BMPs) for Cd and As in acidic soil should be conducted for minimizing uptake of Cd and As into crops.

마산만 저서생태계를 중심으로 연안해역 건강성 평가를 위한 저서생물지수의 적용 (Application of Biotic Indices to Assess the Health Condition of Benthic Community in Masan Bay, Korea)

  • 최진우;서진영
    • Ocean and Polar Research
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    • 제29권4호
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    • pp.339-348
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    • 2007
  • In this work, we compared the characteristics of three benthic biotic indices (BPI, AMBI, BIBI) which indicates the health condition of benthic communities in Masan Bay, Korea where anthropogenic impacts have been concentrated. Also we evaluated the usefulness of these benthic indices and some problems if they were applied to the Korean coastal waters. For this we used the macrozoobenthos data collected using van Veen grab ($0.1\;m^2$) at 21 sites in Masan Bay in February and August 2004. Based on the BPI values, two stations in the inner bay were found in a very hard polluted condition and three stations in the middle bay were also in a highly polluted condition. Only one station located in the bay mouth was in a normal condition. The inner bay stations showed very high AMBI values (${\geq}5.0$), indicating a highly polluted condition. The bay mouth station was assessed in a moderately polluted condition. The overall BIBI values in Masan Bay were in the range between 1.0 and 3.0. The inner bay stations showed low BIBI values (${\leq}2.0$) in the severely degraded condition. The bay mouth station with high BIBI value over 3.0 was assessed as a normal condition. All three benthos indices showed that macrozoobenthic communities in the inner bay were in a seriously polluted condition all year round, and macrobenthic faunas in the bay mouth seemed in a bad healthy condition (slightly polluted) based on AMBI during summer season. These three benthic biotic indices showed the similar assessment result, and thus we consider that each of them is a useful tool for the assessment of coastal benthic ecosystems under the organic enrichment in sediment.

가방 휴대 방법에 따른 보행 시 발의 비례추진력 변화 (Changes of relative impulse of foot on carrying 5 types of schoolbag during level walking)

  • 박수진;김민희;김진상
    • The Journal of Korean Physical Therapy
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    • 제21권3호
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    • pp.61-68
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    • 2009
  • Purpose: The purpose of this study was to analyze the changes of the relative impulse of the foot when carrying 5 types of schoolbag during level walking. Methods: Forty-four normal subjects were divided into 5 groups according to the method of carrying a bag: carrying no bag (condition 1), a backpack (condition 2), a shoulder bag (condition 3), a cross bag (condition 4) and a one-hand bag (condition 5). To evaluate the partial relative impulse, 7 areas were measured on the sole of a foot: the hallux, toe, 1st metatarsal head (Met1) and the 2nd & 3rd metatarsal heads (Met2/3), the 4th & 5th metatarsal heads (Met4/5), mid foot and heel. Repeated one-way analysis of variance (ANOVA) and independent t-tests were used to analyze the statistical data. Results: In the right foot, the relative impulses in every areas revealed no significant difference (p>0.05), however, the relative impulses at Met1, Met2/3, Met4/5 and heel were significantly different between the different conditions (p<0.05). There were significant differences on comparing the relative impulse between left and right foot within one condition, the mid foot in condition 2, as well as the hallux and Met1 in condition 3 (p<0.05). In condition 4, the toe, Met1, Met4/5 and mid foot were significantly different (p<0.05). The values at the hallux, toe and Met1 in condition 5 also were significantly different (p<0.05). Conclusion: These findings showed that the symmetrical relative impulse of the foot was present in the case of carrying a backpack, but there was an extra load on specific regions and asymmetrical relative impulses in the case of carrying a shoulder bag, a across bag and a one-hand bag. (ED note: this abstract is not clear. You need to work on it.)

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THE STRONG MORI PROPERTY IN RINGS WITH ZERO DIVISORS

  • ZHOU, DECHUAN;WANG, FANGGUI
    • 대한수학회보
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    • 제52권4호
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    • pp.1285-1295
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    • 2015
  • An SM domain is an integral domain which satisfies the ascending chain condition on w-ideals. Then an SM domain also satisfies the descending chain condition on those chains of v-ideals whose intersection is not zero. In this paper, a study is begun to extend these properties to commutative rings with zero divisors. A $Q_0$-SM ring is defined to be a ring which satisfies the ascending chain condition on semiregular w-ideals and satisfies the descending chain condition on those chains of semiregular v-ideals whose intersection is semiregular. In this paper, some properties of $Q_0$-SM rings are discussed and examples are provided to show the difference between $Q_0$-SM rings and SM rings and the difference between $Q_0$-SM rings and $Q_0$-Mori rings.

크로스실린더를 이용한 난시정밀검사에서 검사 전 최소착란원 위치에 따른 난시교정값의 변화 (Changes of Corrective Astigmatism Values Depending on Position of Circle of Least Confusion in Astigmatic Refining Test Using Cross Cylinder)

  • 김상엽;이민재;이강천;이태희;문병연;조현국
    • 한국안광학회지
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    • 제20권3호
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    • pp.349-354
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    • 2015
  • 목적: 크로스실린더를 이용한 난시정밀검사에서 망막 상의 최소착란원 위치가 난시교정값에 미치는 영향을 알아보고자 하였다. 방법: 평균나이 $22.24{\pm}2.48$세의 62명(115안)을 대상으로 검사하였다. 방사선시표를 이용한 난시검사 후 최대교정시력이 얻어진 구면굴절력(MPMVA) 상태에서 크로스실린더를 이용한 정밀검사를 실시하였다. 그런 다음 S+0.75 D, S+0.50 D, S+0.25 D, S-0.25 D, S-0.50 D, 그리고 S-0.75 D의 렌즈를 각각 더한 상태(최소착락원의 위치이동)에서 동일한 정밀검사를 실시하고, 얻어진 검사값을 MPMVA 상태에서 얻어진 검사값과 비교하였다. 결과: MPMVA 상태의 검사값과 비교하여 더해준 (+)구면렌즈와 (-)구면렌즈가 증가할수록 축 변화량은 증가하였다. 동일한 검사상태에서 난시굴절력이 높을수록 축 변화량은 감소하였다(p<0.05). MPMVA 상태의 검사값과 비교하여 더해준 (+)구면렌즈가 증가할수록 난시굴절력은 낮게 나타났고(p<0.05), (-)구면렌즈가 증가할수록 높게 나타났다. (+)구면렌즈를 더해준 경우, 동일한 검사상태에서 난시굴절력이 높을수록 검사값의 차이는 더 크게 나타났다. 결론: 올바른 난시교정값을 얻기 위해서 크로스실린더를 이용한 난시정밀검사 전 최소착락원 위치를 정확히 조정하여야 한다.

Effects of performing hip abduction and adduction during bridging exercise on trunk and lower extremity muscle activity in healthy individuals

  • Hwang, Joo Young;Ahn, Woo Young;Kim, Hyo Jae;Woo, Je Hyun;Choi, Woo Jin;Park, Jae Wook;Lee, Mi Young
    • Physical Therapy Rehabilitation Science
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    • 제6권1호
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    • pp.14-19
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    • 2017
  • Objective: To investigate the effect of performing three different bridge exercise conditions on the activities of four different muscles using surface electromyography (sEMG) in healthy young adults. Design: Cross-sectional study. Methods: A total of 20 healthy young adults (10 males, 10 females) voluntarily participated in this study. All subjects randomly performed three different bridge conditions as follows: general bridge exercise, isometric hip abduction (IHAB) with a blue Theraband (Hygenic Corp., USA), and isometric hip adduction (IHAD) with a Swiss ball (Hygenic Corp.). The muscle activities of bilateral erector spinae (ES), gluteus maximus (GM), biceps femoris (BF), and external oblique (EO) muscles during the bridge exercises were measured using sEMG. Subjects performed each of the three bridge conditions three times in random order and mean values were obtained. Results: For bilateral ES and BF, there was a significant increase in muscle activity in the IHAD condition compared to the general bridge and IHAB condition (p<0.05). For bilateral GM, there was a significant increase in muscle activity in the IHAB condition compared to the general bridge condition (p<0.05) and there was a significant increase in muscle activity in the IHAB condition compared to IHAD condition (p<0.05). For left EO, a significant increase was observed in the IHAD condition compared to the general bridge condition (p<0.05). Conclusions: ES and BF muscle activity increases were observed with hip adduction and increased GM activity was observed with hip abduction. These findings may be applicable within the clinical field for selective trunk and lower extremity muscle activation and advanced rehabilitation purposes.

VIABILITY FOR SEMILINEAR DIFFERENTIAL EQUATIONS OF RETARDED TYPE

  • Dong, Qixiang;Li, Gang
    • 대한수학회보
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    • 제44권4호
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    • pp.731-742
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    • 2007
  • Let X be a Banach space, $A:D(A){\subset}X{\rightarrow}X$ the generator of a compact $C_0-semigroup\;S(t):X{\rightarrow}X,\;t{\geq}0$, D a locally closed subset in X, and $f:(a,b){\times}C([-q,0];X){\rightarrow}X$ a function of Caratheodory type. The main result of this paper is that a necessary and sufficient condition in order that D be a viable domain of the semi linear differential equation of retarded type $$u#(t)=Au(t)+f(t,u_t),\;t{\in}[t_0,\;t_0+T],{u_t}_0={\phi}{\in}C([-q,0];X)$$ is the tangency condition $$\limits_{h{\downarrow}0}^{lim\;inf\;h^{-1}d(S(h)v(0)+hf(t,v);D)=0}$$ for almost every $t{\in}(a,b)$ and every $v{\in}C([-q,0];X)\;with\;v(0){\in}D$.