• Title/Summary/Keyword: $C_p$ values

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Dual Sorption of Orange II by Silk Fibroin (견섬유에 대한 Orange II의 이원 수착)

  • 탁태문
    • Journal of Sericultural and Entomological Science
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    • v.24 no.2
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    • pp.81-84
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    • 1983
  • The equilibrium sorption of Orange II by silk fibroin in the range of 50$^{\circ}$, 70$^{\circ}$, 90$^{\circ}C$ and to pH 1.5, 2.2, and 4.0 have been discussed in the light of the dual sorption. Langmuir sorption constant K$\_$L/ and partition coefficient K$\_$P/ were decreased with the increase of the temperature and the pH for the dyeing of silk fibroin with Orange II. Positive values for adsorption entropy were observed. It was found that the values of $\Delta$H$^{\circ}$ is negative for dyeing conditions, and the dyestuff/fibre reaction is therefore exothermic.refore exothermic.

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The Applications of a Multi-metric LEHA Model for an Environmental Impact Assessments of Lake Ecosystems and the Ecological Health Assessments (호수생태계 환경영향평가를 위한 LEHA 다변수 모델 적용 및 생태건강성 평가)

  • Han, Jeong-Ho;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.21 no.3
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    • pp.483-501
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    • 2012
  • The purpose of this study was to apply a multi-metric model of Lentic Ecosystem Health Assessments(LEHA) for environmental impact assessments of Cheongpyung Reservoir during 2005 - 2006 and assessed the ecological model values. The ecosystem model of LEHA was composed of eleven metrics such as biological parameters($B_p$), physical parameters($P_p$), and chemical parameters($C_p$), and determined the rank of ecological health by the criteria. The variables of $B_p$ were metrics of % sensitive species($M_2$, NMS) and insectivore species($M_5$, % $I_n$), which decrease as the water quality degradates, and these metric values were low as 1.5% and 32.4%, respectively. In contrast, the proportions of tolerant species and omnivore species as the other $B_p$ parameters were 43% and 62%, respectively, which indicate a degradation and disturbance of the ecosystem. Riparian vegetation coverage($M_9$, % $V_c$) as a variable of $P_p$, were higher in the 2nd than 1st survey, and decreased toward the dam site from the headwaters. This was due to a habitat simplification(modifications) by frequent bottom dredging of sand and rocks. The variables of $C_p$ were two metrics of specific conductivity($M_{10}$, $C_I$) as an indicator of ionic contents(cations and anions) and the Trophic State Index(TSI) based on chlorophyll-a($M_{11}$, $TSI_{CHL}$) as an indicator of trophic state. These metric values of $C_p$ had high temporal variations, but low spatial variations on the main axis of the reservoir along with the ecological health of a good condition. The environmental impact assessments using the LEHA multi-metric model indicated that the model values of LEHA averaged 30.7 in 1st survey(fair - poor condition) vs. 28 in 2nd survey(poor condition), indicating a temporal variation of the ecological health. The model values of LEHA showed a minimum(28) in the lacustrine zone(S5) and ranged from 29 to 30 in the other locations sampled, indicating a low longitudinal variation. Overall, environmental impact assessments, based on LEHA model, suggest that chemical water quality conditions were in good, but biological conditions were disturbed due to habitat modifications by frequent dredgings in the system.

A Study on Efficiency of Boar Semen Extender KpA for Swine AI Aspects of Storage Temperature and pH Change (돼지 인공수정용 국산 희석액 KpA 의 효용성에 관한 연구 : 보존온도와 pH 변화 측면)

  • 정구민;김선의;신영수;김인철;이장희;임경순
    • Korean Journal of Animal Reproduction
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    • v.23 no.3
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    • pp.257-262
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    • 1999
  • This study was carried out to evaluate the effect of pH and storage temperature on the viability of boar sperm diluted with extender KpA for swine artificial insemination. The results obtained in this experiment were summarized as follows : 1. The viability of boar sperm diluted with KpA was higher than that with BTS during storage and especially more than 60% of sperm viability in KpA was maintained through 6 days. The pH values of all extenders were kept during storage of semens following dilution. 2. The sperm diluted with acidic (pH 6.3~6.8) or alkalic (pH 7.8~8.0) KpA and stored at 4$^{\circ}C$ or 37$^{\circ}C$ were more sensitive in viability than that with neutral pH (6.8~7.3) and at 17$^{\circ}C$ storage. But pH values of all conditions were not increased rapidly. Especially acidic and alkalic diluents were more stable in pH after dilution. Conclusively, extender pH and storage temperature was the important factors for sperm viability. The KpA setting up around neutral pH was the optimal boar semen extender for maintaining liquid semen at 17$^{\circ}C$.

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Correlation of the Speed of Enhancement of Hepatic Hemangiomas with Intravoxel Incoherent Motion MR Imaging (간혈관종의 조영증강속도와 복셀내비결집운동 MR영상과의 상관관계)

  • Yang, Dal Mo;Jahng, Geon-Ho;Kim, Hyun Cheol;Kim, Sang Won;Kim, Hyug-Gi
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.3
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    • pp.208-218
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    • 2014
  • Purpose : To evaluate the relationship between the speed of enhancement of hepatic hemangiomas on gadolinium-enhanced MRI and ADC values by using various parameters, including the D, f, $D^*$ and $ADC_{fit}$ on intravoxel incoherent motion (IVIM) MR Imaging. Materials and Methods: The institutional review board approved this retrospective study. A total of 47 hepatic hemangiomas from 39 patients were included (20 men and 19 women). The hemangiomas were classified into three types according to the enhancement speed of the hepatic hemangiomas on gadolinium-enhanced dynamic T1-weighted images: rapid (Type A), intermediate (Type B), and slow (Type C) enhancement. The D, f, $D^*$ and $ADC_{fit}$ values were calculated using IVIM MR imaging. The diffusion/perfusion parameters and ADC values were compared among the three types of hemangiomas. Results: Both the $ADC_{fit}$ and D values of type C were significantly lower than those of type A (P = 0.0022, P = 0.0085). However, for the f and $D^*$, there were no significant differences among the three types. On DWI with all b values (50, 200, 500 and $800sec/mm^2$), the ADC values of type C were significantly lower than those of the type A (P < 0.012). For b values with $800sec/mm^2$, the $ADC_{800}$ values of the type C hemangiomas were significantly lower than those of type B (P = 0.0021). We found a negative correlation between hepatic hemangioma enhancement type and $ADC_{50}$ (${\rho}=-0.357$, P = 0.014), $ADC_{200}$ (${\rho}=-0.537$, P = 0.0001), $ADC_{500}$ (${\rho}=-0.614$, P = 0.0001), and $ADC_{800}$ (${\rho}=-0.607$, P = 0.0001). Therefore, four ADC values of $ADC_{50}$, $ADC_{200}$, $ADC_{500}$, and $ADC_{800}$ were decreased with decreasing enhancement speed. Conclusion: Hepatic hemangiomas had variable ADCs according to the type of enhancement, and the reduced ADCs in slowly enhancing hemangiomas may be related to the reduced pure molecular diffusion (D).

Effects of Dietary Vitamin E Supplementation on Color Stability, Lipid Oxidation and Reducing Ability of Hanwoo (Korean Cattle) Beef during Retail Display

  • Lee, Sung Ki;Kim, Yong Sun;Liang, Cheng Yun;Song, Young Han
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.10
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    • pp.1529-1534
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    • 2003
  • The effects of dietary vitamin E supplementation (control; 200 IU/head/day, 500 IU/head/day and 1,000 IU/head/day) on color stability, lipid oxidation and total reducing ability in M. longissimus and M. semimembranosus from Hanwoo (Korean cattle) steer during retail display ($3{\pm}1^{\circ}C$, 1,200 lux) were investigated. The $L^{*}$, $a^{*}$, $b^{*}$, $C^{*}$, R630-R580 values and TRA (total reducing ability) of 1,000 IU group were significantly (p<0.05) higher than those of the other groups. The $a^{*}$, $C^{*}$, R630-R580 and TBARS values were significantly (p<0.05) higher in M. longissimus than in M. semimembranosus. The $a^{*}$, $C^{*}$, R630-R580 values and TRA for two beef muscles declined gradually during storage and the decline was more rapid in control and 500 IU groups. Hue angle and metmyoglobin (%) for two beef muscles increased (p<0.05) as display time increased, and 1,000 IU group had a lower rate of metmyoglobin accumulation during retail display. The TBARS values for two beef muscle were significantly (p<0.05) lower in 1,000 IU group than in the other groups over time. Consequently, the meat from 1,000 IU vitamin E-supplemented Hanwoo steer extended retail display life compared to the control and 500 IU/head/day.

Effects of Treadmill Exercise on Respiratory Moisture Losses in Goats of Different Breeds

  • Kasa, I.W.;Thwaites, C.J.;Hill, M.D.;Baillie, N.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.6
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    • pp.842-844
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    • 2000
  • Changes in respiration rate (RR), rectal temperature (RT), respiratory moisture loss (RML), packed cell volume (PCV) and haemoglobin (Hb) were monitored in 2 adults female goats each of the Saanen (S) and Toggenburg (T) breeds during 60 min of exercise (walking at 3 km/h) on a moving-belt treadmill on each of 6 alternate days. A significant $time{\times}breed$ interaction was observed for RR; mean values in Sand T after 60 min of exercise were 130 and 223 /min ($p{\leq}0.01$). The observed time x breed interaction for RT indicated that S was less stressed by exercise than T; mean values after 60 min exercise were 40.4 and $40.8^{\circ}C$ respectively ($p{\leq}0.01$). For RML, the $day{\times}breed$ interaction ($p{\leq}0.001$) indicated that while S had higher values on day 1, thereafter the values for T were higher. The $time{\times}breed$ interaction for RML/breath indicated that values for T declined more rapidly (from 9.4 to 3.1 mgjbreath) than those for S (from 8.3 to 4.1 mgjbreath; ($p{\leq}0.01$). PCV declined during exercise ($p{\leq}0.05$) by 5.5 percentage points. The exercise imposed was stressful in that it led to increases in RR, RT and RML. S was most tolerant of exercise in that it recorded lower values of RT. The fact that the RML/breath was higher during exercies in S apparently allowed it to compensate for a lower RR. Despite higher RR and RML, T also had a higher RT, suggesting either higher muscular heat production during exercise in that breed, or higher sweating losses in S.

pH and Colour Characteristics of Carcasses of Broilers Fed with Dietary Probiotics and Slaughtered at Different Ages

  • Karaoglu, Mevulut;Aksu, M.I.;Esenbuga, N.;Macit, M.;Durdag, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.4
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    • pp.605-610
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    • 2006
  • The objective of the present experiment was to determine the effects of slaughtering at different ages and the use of a commercial probiotic (115-Biogallinox) in broiler diets on the color properties of carcasses, during the first 24 h following slaughter. Ross 308 male broiler chickens obtained from a commercial hatchery were raised to either 35 or 42 days of age. Chickens were fed with different levels of probiotic ($P_0$: 0.0%, $P_1$: 0.1% and $P_2$: 0.2%) containing Saccharomyces cerevisiae during the experimental period. At the end of the trial all birds were slaughtered and then stored at $3^{\circ}C$ for 24 h. The pH and skin colour of carcasses were determined 1, 3, 7, 10, 13, 17 and 24 h after slaughter. Although the use of probiotic and post-mortem ageing time affected the pH (p<0.01), it was not affected by slaughter age (35 and 42 days) (p>0.05). The highest pH values occurred in carcasses of broilers fed 0.2% probiotic. The pH values of carcasses decreased with post-mortem ageing time (p<0.01). Main factors (treatment, slaughter age and post-mortem ageing time) had an effect on colour ($L^*$, $a^*$ and $b^*$) values (p<0.01). $L^*$ values of 42d-old slaughter and $P_2$ group were lower than those of 35d-old slaughter and other probiotic groups. The $a^*$ and $b^*$ values of 35d-old slaughter were lower than those of 42d-old slauhgter. The $a^*$ and $b^*$ values increased during post-mortem ageing (p<0.01). It was determined that changing of the colour traits of broiler carcasses was correlated with probiotic, pH and post-mortem ageing time. Also, it was observed that darkness of carcass colour increased as time progressed.

Cell-meditated studies on blooming and growth of potentially ichthyotoxic Cochlodinium polykrikoides(Dinophyceae)

  • Cho, Eun-Seob
    • Proceedings of KOSOMES biannual meeting
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    • 2007.11a
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    • pp.187-188
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    • 2007
  • The fluctuations of biochemical and molecular activities III the harmful dinoflagellate, Cochlodinium polykrikoides, depending on water temperatures, were studied. In genomic DNA concentration, a similar value of 0.6 was shown at $12^{\circ}C$ and $15^{\circ}C$, but significantly increasing DNA from $18^{\circ}C$ (p<0.05), with a maximum of 1.8 at $24^{\circ}C$. After$24^{\circ}C$, the DNA significantly decreased to 0.6. Likely, the concentrations of RNA and total protein were at their highest values of 1.7 and 0.07 g $mL^1$ at $24^{\circ}C$, respectively. In contrast to ONA, RNA and total protein began to increase at $15^{\circ}C$. Oxygen availability between lower and higher temperatures was significantly different and increased from $18^{\circ}C$ according to light intensity, regardless of wavelengths (p<0.05). At $24^{\circ}C$, the highest value of the maximum electron transport rate (ETRmax), ranging from 537.9 (Ch 1) to 602.5 mol electrons $g^{-1}$ Ch1 a $s^{-1}$ (Ch 4), was also shown. Nitrate reductase (NR) and ATPase activities were at their highest values of 0.11 mol $NO_2^-g^{-1}$ Ch1 a $h^{-1}$ and 0.78 pmol 100 $mg^{-1}$ $at^2$ $4^{\circ}C$, respectively. When the cells cultured at $15^{\circ}C$, NR and ATPase activities significantly increased compared to $12^{\circ}C$ (p<0.05). In an analysis of CHN, the concentration of C and N also significantly increased (p<0.05). However, at $27^{\circ}C$, most of the molecular and biochemical movements were much lower, compared to $24^{\circ}C$. These results suggest that C. polykrikoides is very sensitive biochemical and molecular activities depending on water temperatures. Possibly, it is desirable to estimate at $18^{\circ}C$ the initiation of the massive blooming development of C. polykrikoides. In nature, it will be very difficult to maintain the massive blooms after $24^{\circ}C$ because of the possibility of significantly decreasing the molecular movement and activity of C. polykrikoides.

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Influence of Postconceptional Age on the Renal Biomarkers in Very-Low-Birth-Weight Infants

  • Lee, Ro Sie;Shin, So Young;Jung, Won Ho;Park, Jae Hyun
    • Neonatal Medicine
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    • v.28 no.2
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    • pp.65-71
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    • 2021
  • Purpose: We investigated whether consecutive levels of new emerging renal biomarkers, including serum cystatin C (CysC) and urinary neutrophil gelatinase-associated lipocalin (NGAL)/creatinine (Cr) ratio, were affected by postconceptional age in very-low-birth-weight (VLBW) infants. Methods: Repeatedly measured samples for each infant were divided into four groups according to postnatal age: at birth (stage I), 3 to 7 days postnatally (stage II), 8 to 28 days postnatally (stage III), and >28 days postnatally (stage IV). The association between renal biomarkers and postconceptional age was assessed using Pearson's correlation coefficient, and the mean values of renal biomarkers in the four stages were compared using repeated-measures analysis of variance. Results: For samples measured at birth, serum CysC (r=-0.358, P=0.032) and urinary NGAL/Cr ratio (r=-0.522, P=0.001) were negatively correlated with gestational age, whereas serum Cr (r=0.148, P=0.390) was not. In addition, for all samples measured, serum CysC (r=-0.209, P=0.012), urinary NGAL/Cr ratio (r=-0.536, P<0.001), and serum Cr (r=-0.311, P<0.001) were negatively correlated with postconceptional age. Compared with the mean values of the postnatal age-specific stages, serum CysC showed no significant differences in any of the four stages. However, the urinary NGAL/Cr ratio in stage IV was significantly different from those in stages I to III. Conclusion: Although urinary NGAL/Cr ratio and serum CysC were negatively correlated with postconceptional age considering renal development, serum CysC showed no significant differences in any of the four postnatal age-specific stages. Urinary NGAL/Cr ratio at >28 days postnatally seems to be more affected by postconceptional age than serum CysC in VLBW infants.

Tensile Properties and Thermal Stability of Cellulose Nanofibril/Clay Nanocomposites

  • Park, Byung-Dae;Singh, Adya P.;Um, In Chul
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.1
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    • pp.18-24
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    • 2013
  • This work attempted to fabricate organic/inorganic nanocomposite by combining organic cellulose nanofibrils (CNFs), isolated by 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-mediated oxidation of native cellulose with inorganic nanoclay. The morphology and dimension of CNFs, and tensile properties and thermal stability of CNF/clay nanocomposites were characterized by transmission electron microscope (TEM), tensile test, and thermogravimetry (TG), respectively. TEM observation showed that CNFs were fibrillated structure with a diameter of about $4.86{\pm}1.341nm$. Tensile strength and modulus of the hybrid nanocomposite decreased as the clay content of the nanocomposite increased, indicating a poor dispersion of CNFs or inefficient stress transfer between the CNFs and clay. The elongation at break increased at 1% clay level and then continuously decreased as the clay content increased, suggesting increased brittleness. Analysis of TG and derivative thermogravimetry (DTG) curves of the nanocomposites identified two thermal degradation peak temperatures ($T_{p1}$ and $T_{p2}$), which suggested thermal decomposition of the nanocomposites to be a two steps-process. We think that $T_{p1}$ values from $219.6^{\circ}C$ to $235^{\circ}C$ resulted from the sodium carboxylate groups in the CNFs, and that $T_{p2}$ values from $267^{\circ}C$ to $273.5^{\circ}C$ were mainly responsible for the thermal decomposition of crystalline cellulose in the nanocomposite. An increase in the clay level of the CNF/clay nanocomposite predominately affected $T_{p2}$ values, which continuously increased as the clay content increased. These results indicate that the addition of clay improved thermal stability of the CNF/clay nanocomposite but at the expense of nanocomposite's tensile properties.

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