• Title/Summary/Keyword: equivalent concentration

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Application of Exchange Equations for NH4-K NH4-Ca Equilibria (NH4-K 와 NH4-Ca 평형에 대한 양이온 치환식의 적용)

  • Chung, Jong-Bae;Sa, Tong-Min
    • Korean Journal of Soil Science and Fertilizer
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    • v.28 no.3
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    • pp.218-226
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    • 1995
  • Ion exchange equilibria in bulk and rhizosphere soil collected from peach seedlings were studied to find exchange equations that could be used in chromatographic models dealing with movement and distribution of fertilizer ammonium and exchangeable cations in soil profiles. Soil samples were equilibrated with mixtures of $NH_4Cl$, KCI, and $CaCl_2$ solutions and then extracted with $Sr(NO_3)_2$ solution to determine exchangeable cation compositions at equilibrium. Exchange data were fitted to Vanselow's, Gapon's, and Kerr's equations, but those formulations did not adequately describe the equilibria. An empirical equation of the form : ${\frac{\alpha_i^m}{a_j^n}}=K{\frac{(iX)^{mPi}}{(jX)^{nPj}}}$ which has an exponent on each of the exchangeable cation concentrations could describe the equilibria very well over the range of treatments. In this equation ${\alpha}^i$ and ${\alpha}^j$ are activities of cation i and j with valences m and n respectively. (iX) and (jX) are concentrations of exchangeable cations. Mole or equivalent fractions can be considered as the exchangeable ion concentration unit. Arbitrary constants $P_i$ and $P_j$, and distribution coefficient K can be found with multiple regression for the logarithmic form of the equation.

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A Harmonized Method for Dose-response Risk Assessment Based on the Hazard & Risk Evaluation of Chemicals (HREC) According to the Industrial Safety and Health Act (ISHA) (산업안전보건법 상 유해성.위험성 평가제도 적용을 위한 양-반응 평가의 통일화 방안 연구)

  • Lim, Cheol-Hong;Yang, Jeong-Sun;Park, Sang-Yong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.22 no.3
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    • pp.175-183
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    • 2012
  • Objectives: This study developed a harmonized method for risk assessment based on the Hazard & Risk Evaluation of Chemicals (HREC) according to the Industrial Safety and Health Act (ISHA). Methods: Three preliminary studies, performed during 2010 and 2011 by the Occupational Safety and Health Research Institute and three academic research groups, were compared. The differences in risk assessment, especially in the dose-response assessment method, were analyzed. A new harmonized method for dose-response assessment was suggested and its applicability for the HREC was examined. Results: Considering the various steps of each dose-response assessment, the equivalent steps in quantitative correction, uncertainty factor 2 (UF2) for intra-species uncertainty, and UF3 for the experimental period in the uncertainty correction were relatively high. Using our new method, the total correction values (quantitative correction plus uncertainty correction) ranged from 72~15,789 to 30~60, and the ratio of the threshold limit value (TLV) to the reference concentration decreased from 12.8~1900 to 5.4~11.8. Furthermore, when we performed risk characterization by our new method, hazard quotient (HQ) values for chloroethylene, epichlorohydrin, and barium sulfate became 3.0, 14.1, and 1.13 respectively, whereas three previous studies reported HQ values of 7.1, 4580, and 87.3 considering reasonable maximum exposure (RME) conditions. HQs of the three chemicals were calculated to be 0.6, 2.4, and 0.1 respectively, when compared to their TLVs. Conclusions: Our new method could be applicable for the HREC because the total correction values and the ratio of TLVs were within reasonable ranges. It is also recommended that additional risk management measures be applied for epichlorohydrin, for which the HQ values were greater than 1 when compared with both reference values and the TLV. Our proposed method could be used to harmonize dose-response assessment methods for the implementation of risk assessment based on the HREC according to ISHA.

Effects of Kimchi Supplementation and/or Exercise Training on Body Composition and Plasma Lipids in Obese Middle School Girls (운동 및 김치 보충제 섭취가 비만 여중생의 신체조성 및 혈중지질에 미치는 영향)

  • 백영호;곽정록;김세종;한성섭;송영옥
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.5
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    • pp.906-912
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    • 2001
  • The effects of aerobic exercises and/or supplementation of kimchi on changes of the body composition and plasma lipids of obese middle school girls were studied. Thirty eight girls, 28 obese girls and 10 normal weighed girls, were paricipated. Among obese girls, 8 were assigned to exercise group (FG) 12 were grouped as kimchi group (KG) , and 8 were asked to practice excercise and to take kimchi simultaneously(excercise kimchi group, EKG). Ten girls whose weight is normal asked to remain o their own diet during 6 weeks of experiment (control group, CG)/ EG practiced jogging and rope-jumping for 60 minutes four times a week and KG took 3 g of freeze-dried kimchi packed in a 500 mg capsule daily which is equivalent to 30 g of fresh kimchi, EKC, EG and KG showed beneficial effects on changes of the body composition and plasma lipids compared to those of CG, EG showed greater effect than KG in reducing body fat resulted decrease in BMI, fat mas,. abdominal fat, and triglyceride concentration and increase in HDL-cholesterol. KG seemed to have greater effect on lowering plasma cholesterol and LDL-cholesterol than EG/ But the greatest effects in terms of reduction in weight, BMI fat mass, abdominal fat, total cholesterol, LDL-cholesterol, triglyceride, and increase in HDL-cholesterol were observed from EKG. These results indicate that kimchi supplemenation while practicing excercise might improve the obese state by reducing body fat content as well as reducing plasma lipids.

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Studies on Uptake by Crops of Lead and Reduction of it's Damage -II. Effect of application of calcium and phosphate materials on Pb Solubility in Soil (농작물(農作物)에 대(對)한 납(pb)의 흡수(吸收) 및 피해경감(被害輕減)에 관(關)한 연구(硏究) -II. 석회(石灰)와 인산물질시용(燐酸物質施用)이 토양중(土壤中) 납(pb) 용출량(溶出量)에 미치는 영향(影響))

  • Kim, Kyu Sik;Kim, Bok Young;Han, Ki Hak
    • Korean Journal of Soil Science and Fertilizer
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    • v.19 no.3
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    • pp.217-221
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    • 1986
  • A column test was conducted to find out the effect of application of slaked lime, calcium sulfate, calcium superphosphate, and phosphoric acid on the solubility of lead in soil. The soil was adjusted to 310.8 ppm concentration of Pb and applied with amounts of calcium equivalent to 600, 1000, 2000 ppm as slaked lime; sulfate 144, 288, 432 ppm as calcium sulfate; phosphate 95, 190, 285 ppm as calcium superphosphate and phosphoric acid, respectively. The results obtained are as follows: 1. The increasing application of improvement agents reduced the amounts of water soluble Pb in soil. Phosphoric acid was the most effect among to the treatments. 2. The slaked lime treatment has the highest pH of soil and the lowest at the phosphoric acid one. The soil Eh has a reverse tendency the soil pH. 3. Water soluble Ca, $PO_4$ and $SO_4$ contents increased with increasing application amounts of improvement agents in soil. 4. $1N-NH_4$ OAC soluble Pb content in soil was a decreasing tendency in the order of calcium superphosphate, phosphoric acid, slaked lime, calcium sulfate and control after experiment.

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Land Market of Ukraine: Problems of Legislative Regulation

  • Zemko, Alla;Bukanov, Hryhorii;Zadorozhnia, Halyna;Vinyukova, Olha;Yefimenko, Kristina
    • International Journal of Computer Science & Network Security
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    • v.21 no.12spc
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    • pp.459-462
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    • 2021
  • The article examines the main problems of land market formation in Ukraine. The article is devoted to the study of problems and prospects of land market introduction after the abolition of the ban on alienation. The advantages and disadvantages of lifting the moratorium on the purchase and sale of agricultural land are highlighted. The experience of such European countries as France, Germany, Latvia, Romania and Poland in regulating the market of agricultural lands is analyzed. The historical stages of market formation, features of state policy in this area are considered. The authors found that in these countries the market for agricultural land is well developed and works effectively, which has positive consequences for the economy of these countries. After analyzing the experience, we identified common elements of an effective mechanism for regulating the land market in European countries, which can be implemented in Ukraine. It is emphasized that after the opening of the land market it is necessary to prevent the concentration of a large number of agricultural lands in the hands of one person or close persons and it is necessary to create an effective supervisory body, whose main functions will be supervising sales prevention of speculation in the land market. Emphasis is placed on the need to improve legislation in the field of land, organizational and informational conditions for land reform. The Law of Ukraine "On Amendments to Certain Legislative Acts of Ukraine Concerning the Circulation of Agricultural Land" was analyzed, the adoption of which put an end to the systematic extension of the moratorium on the sale of agricultural land. The positive aspects of such reservations are noted, such as the gradual introduction of the land market, quantitative restrictions, the lower limit of the value equivalent, which can not be less than the normative monetary value. At the same time, the problem is that the lack of an imperative norm on termination of the lease agreement in case of refusal of the lessee to purchase such land at a price not lower than expert assessment, will negatively affect its price formation and actually make the landlord hostage.

Oral Bioavailability for Sub-micron Particle Curcumin (TheracurminCR-033P) and Absorption Rate by Product Composition in Healthy Human Volunteers (서브마이크론 입자 형태 커큐민의 생체 흡수율 및 제품 조성에 따른 흡수율 동등성 연구)

  • Park, Hee Jung;Takahashi, Tsukasa;Ozawa, Hitomi
    • Food Engineering Progress
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    • v.21 no.3
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    • pp.273-279
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    • 2017
  • Curcumin have various health-beneficial properties in numerous studies. However, its bioavailability is low due to its limited intestinal uptake and rapid metabolism. This study aimed to evaluate the pharmacokinetics of newly developed sub-micron particle curcumin with increased water dispersibility (Theracurmin(R) CR-033P). Plasma curcumin levels were measured at 0, 1, 2, 4, 8 h after Theracurmin(R) CR-033P intake using high-performance liquid chromatography. For analyzing pharmacokinetics of Theracurmin(R) CR-033P, eighteen healthy subjects were recruited and received Theracurmin(R) CR-033P at a single oral dose containing curcumin 30 mg. $C_{max}$ was 28.14 ng/ml, and the area under the curve for 8 h was estimated to be 104.36 ng/ml. Based on the area under the plasma concentration (AUC), the bioavailability of sub-micron particle curcumin was higher 22-, 35-, 28-fold than native curcumin in men, women, and all subjects, respectively. For comparing by formulation, seven healthy subjects were recruited and received two type of treatment: (1) existing dosage form 300 mg (contained curcumin 30 mg) ${\times}$ 3 capsule, (2) high dosage form 300 mg (contained curcumin 90 mg) ${\times}$ 1 capsule + placebo 300 mg ${\times}$ 2 capsule. In the cross-over study, there was no significant differences in $C_{max}$ and AUC of plasma curcumin. In conclusion, submicron particle curcumin with increased water dispersibility significantly improved its oral bioavailability and women absorbed curcumin more effectively than men. Different formulation of Theracurmin(R) CR-033P has shown equivalent to the reference in terms of pharmacokinetics.

Effects of rice straw fermented with spent Pleurotus sajor-caju mushroom substrates on milking performance in Alpine dairy goats

  • Fan, Geng-Jen;Chen, Mei-Hsing;Lee, Churng-Faung;Yu, Bi;Lee, Tzu-Tai
    • Animal Bioscience
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    • v.35 no.7
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    • pp.999-1009
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    • 2022
  • Objective: To improve the feeding value of rice straw (RS), this study evaluated the potential of rice straw fermented with Pleurotus sajor-caju (FRS) as dairy goat feed. Methods: Spent Pleurotus sajor-caju mushroom substrate was used as fungi inoculum to break the lignocellulose linkage of rice straw, which was solid-fermented at 25℃ to 30℃ for 8 weeks. The ruminal degradation of pangolagrass hay (PG), FRS, and RS were measured in situ for 96 hours in three dry Holstein cows, respectively. Effect of fungi fermented RS on milking performance was studied in feeding trials. A total of 21 Alpine goats a trial were divided into 3 groups: a control group in which PG accounted for 15% of the diet dry matter, and FRS or RS was used to replace the PG in the control group. Goats were fed twice a day under two 28-day trial in individual pens. Meanwhile, a 3×3 Latin square trial (14 days/period) was conducted to study the rumen digestion of three diets by using three fistulated dry goats. Rumen contents were collected for metabolite analyses every one to three hours on the last two days. Results: In situ study showed that fermentation could elevate the rumen degradable fraction and effective degradability of RS (p<0.05). Effective degradability of FRS dry matter was significantly increased from 29.5% of RS to 41.7%. Lactating trial results showed that dry matter intake and milk yield in the PG group and FRS group were similar and higher than those in RS group (p<0.05). The concentration of propionic acid and total volatile fatty acid in the RS group tended to be lower than those in PG group (p<0.10). There were no differences in rumen pH value and ammonia nitrogen level among the groups tested. Conclusion: Fermentation of rice straw by spent Pleurotus sajor-caju mushroom substrate could substantially enhance its feeding value to be equivalent to PG as an effective fiber source for dairy goat. The fermented rice straw is recommended to account for 15% in diet dry matter.

Development of a lateral flow dipstick test for the detection of 4 strains of Salmonella spp. in animal products and animal production environmental samples based on loop-mediated isothermal amplification

  • Wirawan Nuchchanart;Prapasiri Pikoolkhao;Chalermkiat Saengthongpinit
    • Animal Bioscience
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    • v.36 no.4
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    • pp.654-670
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    • 2023
  • Objective: This study aimed to develop loop-mediated isothermal amplification (LAMP) combined with lateral flow dipstick (LFD) and compare it with LAMP-AGE, polymerase chain reaction (PCR), and standard Salmonella culture as reference methods for detecting Salmonella contamination in animal products and animal production environmental samples. Methods: The SalInvA01 primer, derived from the InvA gene and designed as a new probe for LFD detection, was used in developing this study. Adjusting for optimal conditions by temperature, time, and reagent concentration includes evaluating the specificity and limit of detection. The sampling of 120 animal product samples and 350 animal production environmental samples was determined by LAMP-LFD, comparing LAMP-AGE, PCR, and the culture method. Results: Salmonella was amplified using optimal conditions for the LAMP reaction and a DNA probe for LFD at 63℃ for 60 minutes. The specificity test revealed no cross-reactivity with other microorganisms. The limit of detection of LAMP-LFD in pure culture was 3×102 CFU/mL (6 CFU/reaction) and 9.01 pg/μL in genomic DNA. The limit of detection of the LAMP-LFD using artificially inoculated in minced chicken samples with 5 hours of pre-enrichment was 3.4×104 CFU/mL (680 CFU/reaction). For 120 animal product samples, Salmonella was detected by the culture method, LAMP-LFD, LAMP-AGE, and PCR in 10/120 (8.3%). In three hundred fifty animal production environmental samples, Salmonella was detected in 91/350 (26%) by the culture method, equivalent to the detection rates of LAMP-LFD and LAMP-AGE, while PCR achieved 86/350 (24.6%). When comparing sensitivity, specificity, positive predictive value, and accuracy, LAMP-LFD showed the best results at 100%, 95.7%, 86.3%, and 96.6%, respectively. For Kappa index of LAMP-LFD, indicated nearly perfect agreement with culture method. Conclusion: The LAMP-LFD Salmonella detection, which used InvA gene, was highly specific, sensitive, and convenient for identifying Salmonella. Furthermore, this method could be used for Salmonella monitoring and primary screening in animal products and animal production environmental samples.

Studies on the red-yellow soil in Honam rolling area - Improvement of soil fertility - (호남야산(湖南野山)에 분포(分布)하고 있는 적황색(赤黃色)에 관(關)한 연구(硏究) - 토양비옥도(土壤肥沃度) 증진(增進)에 관(關)하여 -)

  • Chae, Sang Suk;Chang, Young Sun;Lee, Hwa Soo;Hong, Chong Woon
    • Korean Journal of Soil Science and Fertilizer
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    • v.7 no.1
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    • pp.29-34
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    • 1974
  • On a newly reclamed acidic Song-jong soil (soil of a member of fine loamy, mesic family of Hapludults) an experiment was carried out to find out the proper measure of the improvement of soil fertility with soybean as test crop. Results are summarized as follow: 1. Application of compost (1 ton/10a), lime (lime requirement)and fused phosphate (equivalent to 5% of the phosphate fixation coefficient)resulted in the increase of soybean yield by 93.3% over the check plot (N: 6kg/10a, $P_2O_5$: 9kg/10a, $K_2O$: 6kg/10a). The application of fused phosphate at the level of 5% of phosphate fixation coefficient N (6kg/10a) and K(6kg/10a) brought the yield increase by 62.7% over the check plot. However, although the pH of the soil was adjusted to 7.0 by liming, the application of lime with moderate dose of phosphate ($P_2O_5$: 9kg/10a) did not increase the yield of soybean significantly. And the application of fused phosphate at the level of 5% of phosphate fixation coefficient increased the available soil P from 14 ppm to around 100 ppm as tested after harvest. 2. Application of compost (1 ton/10a) increased the organic matter content of soil by 0.8% when tested after harvest. While, the application of rice straw (0.5 ton/10a) did not alter the soil organic matter content. The CEC of the soil tested after havest found incereased significantly by the addition of lime and compost. 3. Plant analysis revealed that the $K_2O/Ca+Mg$ is better correlated with the yield than the absolute concentration of $K_2O$ in plant tissue. Between the concentration of $P_2O_5$ in plant tissue and the yield of soybean, a typical C-curve relationship was observed, indicating that in this particular soil, phosphate was the primary growth liming factor.

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Electrode Characteristics of K+ Ion-Selective PVC Membrane Electrodes with AC Impedance Spectrum (AC 임피던스 분석법을 이용한 K+ 이온선택성 PVC막 전극 특성)

  • Kim, Yong-Ryul;An, Hyung-Hwan;Kang, An-Soo
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.870-877
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    • 1998
  • With impedance spectrum measurements, impedance was studied in the interface between sample solutions for $K^+-ion$ selective PVC membrane electrode containing neutral carriers [dibenzo-18-crown-6 (D18Cr6) and valinomycine (Val)]. Response characteristics of electrode were examined by measuring AC impedance spectra that were resulted from the chemical structure and the content of carrier, variation of plasticizer, membrane thickness, doping of base electrolytes, and concentration variation of sample solution. Transport characteristics of PVC membrane electrode were also studied. It was found that the equivalent circuit for the membrane in $K^+$ solution could be expressed by a series combination of solution resistance and a parallel circuit consisting of the bulk resistance and geometric capacitance of the membrane system. But the charge transfer resistance and Warburg resistance were overlapped a little in the low concentration and low frequency ranges. The carrier, D18Cr6 was best for electrode and impedance characteristics, and ideal electrode characteristics were appeared especially in case of doping of the base electrolyte[potassium tetraphenylborate(TPB)]. The optimum carrier content was about 3.23 wt% in case of D18Cr6 and Val. DBP was best as a plasticizer. As membrane thickness decreased the impedance characteristics was improved, but electrode characteristics were lowered for membrane thickness below the optimum. In the case of D18Cr6, the selectivity coefficients by the mixed solution method for the $K^+$ ion were the order of $NH_4{^+}>Ca^{2+}>Mg^{2+}>Na^+$.

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