• Title/Summary/Keyword: Interaction Effect

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Structure and Variation of Tidal Flat Temperature in Gomso Bay, West Coast of Korea (서해안 곰소만 갯벌 온도의 구조 및 변화)

  • Lee, Sang-Ho;Cho, Yang-Ki;You, Kwang-Woo;Kim, Young-Gon;Choi, Hyun-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.100-112
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    • 2005
  • Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

Effects of hydrocolloids on wheat flour rheology (Hydrocolloid의 첨가가 밀가루 반죽의 특성에 미치는 영향)

  • 임경숙;황인경
    • Korean journal of food and cookery science
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    • v.15 no.3
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    • pp.203-209
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    • 1999
  • The effect of several hydrocolloids on the rheological behavior of wheat flour was investigated. The influence of the selected hydrocolloids (alginate, carrageenan, CMC, guar, locustbean and xanthan) on wheat flour was tested by using two different techniques; amylograph and texture analyzer. In order to have a general overview of their effects hydrocolloids were chosen from different sources implying a broad diversity of chemical structures. The hydrocolloid addition decreased the brightness(L) but increased yellowness(b). The interaction between hydrocolloid and flour produces a slight modification of the amylogram parameters, being the most clearly affected parameter breakdown, which is increased by carrageenan, guar and xanthan. Hardness and cutting force were augmented by hydrocolloid addition, while springeness was decreased except guar and locustbean. In summary, when looking for the improvement of the noodle texture, guar, locustbean are the best candidate additives due to their effects on pasting and texture properties. These hydrocolloids increase the hardness, cutting force, gumness, chew-ness, so were thought to increase the eating quality. So, each tested hydrocolloid affected in a different way the rheological properties of wheat flour, the results obtained are important for the appropriate use of these hydrocolloid as ingredients in the noodle making process.

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Kinetic Studies on the Reaction of the Homobimetallic Anion, M+5-MeCp)Mn(CO)2Mn(CO)5-(M+=Na+, PPN+) with Allyl Chloride (동종이핵착물인 M+5-MeCp)Mn(CO)2Mn(CO)5-(M+=Na+, PPN+)와 염화알릴간의 반응에 대한 반응속도론적 연구)

  • Park, Yong-Kwang;Yun, Dong-Shin
    • Journal of the Korean Chemical Society
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    • v.48 no.5
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    • pp.473-482
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    • 2004
  • The homobimetallic anion, $M^+({\eta}^5-MeCp)Mn(CO)_2Mn(CO)_5^-(M^+=Na^+,\;PPN^+)$was disrupted by CH2CHCH2Cl in THF at various temperatures ($20^{\circ}C~50^{\circ}C$) under the pseudo 1st order reaction conditions where excess of allyl chloride was employed under a nitrogen atmosphere. This homobimetallic anion seems to be involved in a concerted reaction mechanism in which a four-centered transition state is proposed. After undergoing the transition state, this reaction eventually leads to (MeCp)Mn$(CO)_3$ on addition of CO and $({\eta}^1-allyl)Mn(CO)_5$, respectively. However, in case of $Na^+$ analog, $Na^+$ may play a novel counter ion effect on the disruption reaction either by transferring one terminal CO from the $Mn(CO)_5$ moiety on to the $({\eta}^5-MeCp)Mn(CO)_2$of the corresponding homobimetallic complex, eventually resulting in $({\eta}^5-MeCp)Mn(CO)_3$ or through the interaction between $Na^+$ and the leaving group (Cl) of allyl chloride. This reaction is of overall second order with respect to homobimetallic complex with the activation parameters (${\Delta}H^{\neq}=17.15{\pm}0.17kcal/mol,\;{\Delta}S^{\neq}=-9.63{\pm}0.10$ e.u. for $Na^+$ analog; ${\Delta}H^{\neq}=22.13{\pm}0.21 kcal/mol,\;{\Delta}S^{\neq}=9.74{\pm}0.19$ e.u. for $PPN^+$ analog reaction).

Effect of sputtering conditions on the exchange bias and giant magnetoresistance in Si/Ta/NiFe/CoFe/Cu/CoFe/FeMn/Ta spin valves (스파터링 조건이 FeMn계 top 스핀 밸브의 exchange bias 및 자기적 특성에 미치는 영향)

  • Kim, K.Y.;Shin, K.S.;Han, S.H.;Lim, S.H.;Kim, H.J.;Jang, S.H.;Kang, T.
    • Journal of the Korean Magnetics Society
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    • v.10 no.2
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    • pp.67-73
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    • 2000
  • Top spin valve samples with a structure Ta/NiFe/CoFe/Cu/CoFe/FeMn/Ta were deposited on a Si(100) substrate by changing d.c. magnetron sputtering conditions and the exchange-bias and magnetic properties of samples were investigated. The Exchange field, H$\_$ex/ increased with increase of sputtering power of FeMn from 30 to 150 W and CoFe from 30 to 100 W deposited on the Cu, the increase of H$\_$ex/ was found due to the improvement of preferred orientation of (111) FeMn phase from XRD results. In the case of Cu, H$\_$ex/ decreased with the increase of sputtering pressure ranging from 1 to 5 mTorr. The relationship between exchange field and resistance was investigated, spin valve samples with a large exchange field showed the lower resistance, which was strongly dependent on the good crystallinity and grain size increase as well as lower scattering effects. The Cu thickness was changed from 22 to 38 $\AA$ for Si/Ta/NiFe/CoFe/Cu(t), 30 W/CoFe, 100 W/FeMn, 100 W/Ta spin valve structures, MR ratio of 6.5 % and exchange field of about 190 Oe were obtained for the sample with Cu of 22 $\AA$ thickness. The increase of exchange field with decrease of Cu thickness was explained by FM/AFM spin-spin interaction.

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Assessment of Groundwater Contamination Using Geographic Information System (지리정보시스템을 이용한 지하수 오염 평가)

  • 전효택;안홍일
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.3
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    • pp.129-140
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    • 1998
  • In this study two sites were selected to investigate groundwater contamination and spatial relationship between pollution level and its source. One is the Asan area, agricultural district where pollution sources are scattered. The other is the Gurogu area of Seoul city, industrial district where industrial complex and residential areas are located. Groundwater samples collected from these districts were analysis for chemical constituents. The attribute value files of the chemical constituents of groundwater and the spatial layers have been constructed and the pollution properties have been investigated to find out spatial relationships between the groundwater constituents and pollution sources using CIS. Relatively high contents of Si and HCO$_3$ in groundwater from the Asan area reflect the effect of water-rock interaction, whereas high contents of Cl, NO$_3$, SO$_4$and Ca in groundwater from the Gurogu area are due to the pollution of various sources. Pollution over the critical level of Korean Dinking Water Standard has been investigated from 15 sampling sites out of 40 in the Asan area, and 33 sampling sites out of 51 in the Gurogu area. There is pollution of NO$_3$, Cl, Fe, Mn, SO$_4$and Zn in groundwater from the Gurogu area, and that of NO$_3$, SO$_4$and Zn in groundwater from the Asan area. Principal pollution in both areas is NO$_3$contamination. Deep groundwater from the Asan area is not contaminated with NO$_3$except for one site and most of shallow groundwater near the potential point sources such as factory and stock farm is contaminated seriously. Groundwater from the Gurogu area has been already polluted seriously considering the fact of contamination of deep groundwater. This study reports a spatial relationship between the pollution level and pollution source using GIS.

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Effect of the Dietary Composition (quantitative ratio between carbohydrate and protein) and the Rearing Temperature during the 4th Moulting Period on Proteinase Activity of Digestive Juice and Sucrase Activity of Midgut Tissue in the Silkworm, Bombyx mori L. (가잠유충의 소화액 Proteinase 및 중장조직 Sucrase의 활성에 미치는 사료조성(당과 단백질과의 량비) 및 4 면기보호온도의 영향)

  • 문재유
    • Journal of Sericultural and Entomological Science
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    • v.15 no.1
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    • pp.9-14
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    • 1973
  • This study has been carried out to investigate proteinase activity of digestive juice and sucrase activity of midgust tissue in the 5th day of the 5th instar influenced by the dietary composition (quantitative ratio between carbohydrate and protein) and tile rearing temperature during the 4th moulting period. The larvae grew on three kinds of semi-synthetic diet. The A-diet has more carbohydrate than the others, the B-diet has carbohydrate in 1 : 2 with protein, and the C-diet has more protein than the others. All the diets were kept at 16$^{\circ}C$, 25$^{\circ}C$ and 33$^{\circ}C$ during the 4th moulting period. Proteinase activity of digestive juice at the 5th day of the 5th instar was analyzed by Anson's hemoglobin method. Sucrase activity of midgut tissue at the 5th day of 5th instar was analyzed by Somogyi-Nelson's method. The results were as follows. 1. The dietary composition influencing contents of blood sugar was not related to the rearing temperature during the 4th moulting period. The contents of blood sugar appeared to increase in A-diet, B-diet and C-diet order, while proteinase and sucrase activity were stronger in C-diet, B-diet and A-diet order. 2. All kinds of diets showed almost the same fact that proteinase activity at 16$^{\circ}C$ was stronger than that at 32$^{\circ}C$. 3. It was found that sucrase activity became gradualy stronger at 32$^{\circ}C$, 25$^{\circ}C$ and 16$^{\circ}C$ in order in all kinds of diets. 4. There was an interaction in proteinase activity between the dietary composition and the rearing temperature in male larval digestive juice during the 4th mouiting period. On the other hand, there was an inter-acion in sucrase activity between the dietary composition and the rearing temperature in both female and male larval midgut tissue during the 4th moulting period.

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True Digestibility of Phosphorus in Different Resources of Feed Ingredients in Growing Pigs

  • Wu, X.;Ruan, Z.;Zhang, Y.G.;Hou, Y.Q.;Yin, Y.L.;Li, T.J.;Huang, R.L.;Chu, W.Y.;Kong, X.F.;Gao, B.;Chen, L.X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.1
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    • pp.107-119
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    • 2008
  • To determine the true digestible phosphorus (TDP) requirement of growing pigs, two experiments were designed with the experimental diets containing five true digestible P levels (0.16%, 0.20%, 0.23%, 0.26% and 0.39%) and the ratio of total calcium to true digestible P (TDP) kept at 2:1. In Experiment 1, five barrows (Duroc${\times}$Landrace${\times}$Yorkshire) with an average initial body weight of 27.9 kg were used in a $5{\times}5$ Latin-square design to evaluate the effect of different dietary P levels on the digestibility and output of P and nitrogen. In Experiment 2, sixty healthy growing pigs (Duroc${\times}$Landrace${\times}$Yorkshire) with an average body weight (BW) of 21.4 kg were assigned randomly to one of the five dietary treatments (12 pigs/diet), and were used to determine the true digestible phosphorus (TDP) requirement of growing pigs on the basis of growth performance and serum biochemical indices. The results indicated that the true digestibility of P increased (p<0.05) linearly with increasing dietary TDP level below 0.26%. The true P digestibility was highest (56.6%) when dietary TDP was 0.34%. Expressed as g/kg dry matter intake (DMI), fecal P output increased (p<0.05) linearly with increasing P input. On the basis of g/kg fecal dry matter (DM), fecal P output was lowest for Diet 4 and highest (p<0.05) for Diet 5. The apparent digestibility of crude protein (CP) did not differ (p>0.05) among the five diets, with the average nitrogen output of 12.14 g/d and nitrogen retention of 66% to 74% (p>0.05), which suggested that there was no interaction between dietary P and CP protein levels. During the 28-d experimental period of Experiment 2, the average daily gain (ADG) of pigs was affected by dietary TDP levels as described by Eq. (1): $y=-809,532x^4+788,079x^3-276,250x^2+42,114x-1,759$; ($R^2=0.99$; p<0.01; y = ADG, g/d; x = dietary TDP, %), F/G for pigs by Eq. (2): $y=3,651.1x^4-3,480.4x^3+1,183.8x^2-172.5x+10.9$ ($R^2=0.99$; p<0.01; y = F/G; x = dietary TDP, %), and Total P concentrations in serum by Eq. (3): $y=-3,311.7x^4+3,342.7x^3-1,224.6x^2+195.6x-8.7$ (R2 = 0.99; p<0.01; y = total serum P concentration and x = dietary TDP, %). The highest ADG (782 g/d), the lowest F/G (1.07) and the highest total serum P concentration (3.1 mmol/L) were obtained when dietary TDP level was 0.34%. Collectively, these results indicate that the optimal TDP requirement of growing pigs is 0.34% of the diet at a total Ca to TDP ratio of 2:1.

An Application Effect of Rhythmic Movement Program for the Health Promotion in the Elderly (노인의 건강증진을 위한 율동적 운동프로그램의 적용효과)

  • 이숙자
    • Journal of Korean Academy of Nursing
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    • v.30 no.3
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    • pp.776-790
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    • 2000
  • Every year the number of the elderly increases in Korea thanks to the improvemen of social and economical levels and the development of medicine. However, many problems such as insufficent care and the isolation of the elderly have been commonplace. This trend exists not only because of increased lifespan but also the changing social structure of the nuclear family. Accordingly, inspite of the development of medicine, geriatric diseases including circulatory diseases are increasing in proportion of elderly population, as well as the severity. Therefore, it is important to emphasize that health care programs provide the best possible health care and functional capacities in terms of healthy elderly lifestyles. Especially, the phenomena of aging and geriatric diseases taking place with the elderly naturally are affected by lifestyle and the drastic changes in exercise patterns. This study aims to improve geriatric health by introducing a rhythmic movement program for the elderly to estabilish a health-promoting self-care system and by developing quality of life, perceived health status, their physical and physiological functions and emotional state. The theoretical framework used in this dissertation is derived from the Health-Promoting Self-Care System Model (Simmons, 1990), which integrates the Self-Care Deficit Nursing Theory (Orem, 1985), the interaction model of Client Health Behavior (Cox, 1982) and the Health Promotion Model (Pender, 1987). As a quasi-experimental design, the nonequivalent control group pretest-posttest design is utilized for this study. The subjects of this study consist of 64 people, over 65 years old who live in 2 nursing homes for the aged located in S city , Kyong-gi province and volunteered for this study from July, 12, 1999 to September, 17, 1999. They are divided into two groups:33 in the experimental group and 31 in the control group. The experimental group particpated in the Rhythmic Movement Program at the nursing home, which was comprised of 45 minutes a session, 5 sessions a week during 9 weeks. In order to measure the results of the Rhythmic Movement Program, aspects of perceived health status, balance, flexibility, grip strength, leg strength, heart rate, blood pressure, depression, anxiety and the quality of life were measured before and after participating in the Rhythimic Movement Program for the experimental group after 9 weeks, as well as the control group. The collected data were processed by SPSS PC+ and analyzed by the X2 test, t-test, ANCOVA and the Pearson Correlation Coefficient. The results of this study are as follows: 1. The perceived health status conditions in the experimental group show statistically significant improvement when compared to the control group (F=17.51, p=.000). 2. The physical and physiological functions, that is, balance (F=17.51, p=.000), flexibility (F=8.01, p=.006), grip strength (F=3.21, p=.018) and leg strength (F=25.78, p=.000) in the experimental group are higher than the control group. The vital signs, that is, the number of heart rate (F=.022, p=.884), systolic pressure (F=1.73 p=.193), and diastolic pressure (F=2.74, p=.103) in the experimental group compared to the control group decreased, but doesn't show statistically significant differences. Immune responses (F=5.13, p=.003) showed statistically significant increases in the experimental group when compared to the control group. 3. The emotional state are improved, that is, degree of depression (F=11.56, p=.001) and degree of anxiety (F=9.14, p=.004) in the experimental group showed statistically significant decreases. 4. The quality of life in the experimental group (F=3.03, p=.037) showed statistically significant differences compared to the control group. 5. The observations of the relationships among the perceived health status, emotional state , the quality of life, the relationships between the perceived health status, the degree of depression (r=-.653, p=.000) and the degree of anxiety (r=-.786, p=.000) were in contrary propotions, while the relationships between the perceived health status and the quality of life (r=.234, p=.008) were in direct propotion. In conclusion, the Rhythmic Movement Program used in this study for geriatric nursing care is simple and safe for application to the elderly and shows significant effects by implementing 5 sessions a week for 9 weeks. The Rhythmic Movement Program improves the quality of life, maintains as well as improves the physical and physiological fuctions and emotional state, therefore this program is strongly recommended for positive applications for independant geriatric nursing health care.

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Characteristics of Pinewood Nematode Trapping by Nematophagous Arthrobotrys spp. (선충포획성 Arthrobotrys속균에 의한 소나무재선충 포획 특성)

  • Lee, Gak-Jung;Koo, Chang-Duck;Sung, Joo-Han
    • The Korean Journal of Mycology
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    • v.36 no.2
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    • pp.153-162
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    • 2008
  • Pinewood nematode (PWN) trapping by nematophagous fungi, Arthrobotrys conoides, A. dactyloides and A. oligospora and the fungal growth were characterized. The three Arthrobotrys species each was inoculated into the PWN cultured on Botrytis cinera fungal colony on potato dextrose agar (PDA). The effects of temperature, pH, PWN inoculation density and nutrients on the growth of the three Arthrobotrys spp were measured. A. conoides grew fast, 13.9 mm/day while A. dactyloides grew slow, 3 mm/day. PDA medium was the best for the fungal growth at $25^{\circ}C$ and pH 4.5. The Arthrobotrys spp growth was stimulated by 500 nematodes inoculation but not by 1000 inoculation. A. dactyloides did not grow below pH 4.5 and at high PWN density. A. conoides and A oligospora formed trapping organs with thick constricting hyphal network only when PWN present, while A. dactyloides formed the organ with circular hyphae constitutively. A. conoides formed trapping organs faster than A. oligospora did. The nematode trapping hyphae of the fungi penetrated into PNW inside to form many tiny infection bulbs and to digest the nematode. However, A. dactyloides formed a few trapping organs but no trapping was observed. Infection rate of PWN was 95% by A. conoides, 80% by A. oligospora and 92% by the combination inoculation of A. conoides and A. oligospora. In contrast A. dactyloides increased PWN density without infecton. There was no interaction effect in any combination inoculation of the three Arthrobotrys spp. A. conoides enhanced PWN infection rate by rapid hyphal growth and early trapping, while A. oligospora did it by increasing hyphal density. In conclusion A. conoides is the most effective in both hyphal growth and infection, and thus these characteristics can be utilized as a biological control of PWN.

Interactions among Carbon Isotope Discrimination, Water Use Efficiency and Nitrogen Nutrition in Wheat and Barley (밀과 보리에 있어서 탄소동위원소차별, 수분이용효율, 질소영양간의 상호작용)

  • Young Kil, Kang;Richard A., Richards;Anthony G., Condon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.3
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    • pp.318-331
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    • 1996
  • Large and small seeds (44 and 22 mg per caryopsis) of a spring wheat (cv. Kulin) and a spring barley (cv. Skiff) were sown at two nitrogen rates (equivalent to 10 and 32 g m$^{-2}$ ) in well-watered pots under outdoor conditions to determine the effects of seed size and nitrogen (N) nutrition on water use efficiency (WUE) and carbon isotope discrimination ($\Delta$) and to evaluate interaction among $\Delta$, WUE and N nutrition in wheat and barley. Barley produced, on average, 105% more biomass (root+shoot dry weight) than wheat at stem elongation because of early vigor. By anthesis this difference had disappeared as wheat had 16% more biomass than barley which headed 3 days earlier. Compared to plants grown from small seed, plants grown from large seed had much greater biomass in wheat than in barley at stem elongation and anthesis. Higher N nutrition increased average biomass of wheat and barley by 40 and 31%, respectively, at anthesis. Barley had 35 and 20% greater WUE (biomass gained/transpiration) than wheat at stem elongation and anthesis, respectively, and 2.0 to 3.6% lower $\Delta$ in aboveground shoots depending on growth stages and plant parts than wheat which had a greater stomatal conductance than barley. Seed size had a variable effect on WUE and did not affected $\Delta$ values. Water use efficiency was not affected by N rate at stem elongation in wheat and barley whereas WUE was increased 2 and 7%, respectively, in wheat and barley at anthesis with increasing N from 10 to 32 g m$^{-2}$ . High N plants had about 2.5% lower $\Delta$ values regardless of growth stages than low N plants across species and seed sizes. Carbon isotope discrimination was negatively correlated with WUE at anthesis but not at stem elongation.

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