• Title/Summary/Keyword: $^{15}N$ recovery

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A Study on the Preparation of Durable Softening Water Repellent by Blending Acrylic Copolymer and Fatty Carbamide;Water Repelling Finish of PET Fabrics (아크릴 공중합체와 지방산 카르바미드의 블렌딩에 의한 내구유연발수제의 제조에 관한 연구;V. PET 직물에의 발수가공)

  • Im, Wan-Bin;Kim, Seong-Kil;Park, Hong-Soo
    • Journal of the Korean Applied Science and Technology
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    • v.13 no.3
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    • pp.137-144
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    • 1996
  • Durable softening water repellents such as PODCW, PDDCW, and PEDCW were prepared by blending cationized polymers, fatty carbamide, waxes, and emulsifiers. The cationized polymers included poly (octadecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PODC], poly (n-dodecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PDDC]and poly (2-ethylhexyl methacrylate-co-2-diethylaminoethyl methacrylate) [PEDC]. After the PET fabrics were treated with these water repellents, water repellency, softness, and durability of the PET fabrics were examined by various methods : water repellency by the hydrostatic pressure and the contact angle methods, softness by crease recovery and tearing strength, and durability by washability, respectively. Rating of water repellency of PET fabrics treated with PODCW was $80^{+}$, but those treated with PDDCW and PEDCW were not high enough to be used in industry.

Ex-situ Remediation of a Contaminated Soil of Fe Abandoned Mine using Organic Acid Extractants (유기산 추출에 의한 철 폐광산 오염토양의 복원)

  • 정의덕;강신원;백우현
    • Journal of Environmental Science International
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    • v.9 no.1
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    • pp.43-47
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    • 2000
  • A study on the remediation of heavily for ion contaminated soils from abandoned iron mine was carried out, using ex-situ extraction process. Also, oxalic acid as a complex agent was evaluated as a function of concentration, reaction time and mixing ratio of washing agent in order to evaluate Fe removability of the soil contaminated from the abandoned iron mine. Oxalic acid showed a better extraction performance than 0.1N-HCl, i.e., the concentrations of Fe ion extracted from the abandoned mine for the former at uncontrolled pH and the latter were 1,750 ppm and 1,079 ppm, respectively. The optimum washing condition of oxalic acid was in the ratio of 1:5 and 1:10 between soil and acid solution during l hr reaction. The total concentrations of Fe ion by oxalic acid and EDTA at three repeated extraction, were 4,554 ppm and 864 ppm, respectively. The recovery of Fe ions from washing solution was achieved, forming hydroxide precipitation and metal sulfide under excess of calcium hydroxide and sodium sulfide. In addition, the amounted of sodium sulfide and calcium hydroxide for the optimal revovery of Fe were 15g/$\ell$ and 5g/$\ell$ from the oxalic acid complexes, respectively.

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Circardian rhythm of cardiac nonlinear dynamics in healthy human

  • Yum, M.K.;Kim, N.S.;Oh, J.W.;Kim, C.R.;Lee, J.H.;Kim, S.K.;Lee, J.M.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.323-326
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    • 1997
  • In this study, we investigated the circardian rhythm of complexity of cardiac dynamics in humans. Dynamic 24-hour electrocardiographic recordings were obtained from 30 healthy ambulant subjects aged 41 to 50 years. or each recordings, normalized low frequency (0.04-0.1 hertz) and high frequency (>0.15 hertz) component are calculated. our different indexes obtained from separate algorithms of nonlinear dynamics - approximate entropy, correlation dimension, Lyapunov exponent and fractal dimension - were calculated. During early morning, low frequency component rose rapidly with concomitant withdrawl of high frequency component. All the our indexes of nonlinear dynamics showed remarkably same circardian rhythm: an early morning dip preceded by a steep decline during late night, a gradual recovery during evening and a peak around midnight. These data indicate that the simultansous losses of all of the our different mechanisms of nonlinear control of heart rate during early morning, concomitent with the surge of symapathetic activity and reduction of vagal activity, may contribute to the increased incidence of cardiovascular events during morning hours.

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Liquid Chromatography-Tandem Mass Spectrometry Analysis of Riboflavin in Beagle Dog Plasma for Pharmacokinetic Studies

  • Jeong, Hyeon Myeong;Shin, Beom Soo;Shin, Soyoung
    • Mass Spectrometry Letters
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    • v.11 no.1
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    • pp.10-14
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    • 2020
  • Riboflavin is a water-soluble vitamin, which serves as a precursor to flavin mononucleotide and flavin adenine dinucleotide. This study aimed to develop a simple and rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis for the quantification of riboflavin in the Beagle dog plasma. This method utilized simple protein precipitation with acetonitrile and 13C4, 15N2-riboflavin was used as an internal standard (IS). For chromatographic separation, a hydrophilic interaction liquid chromatography (HILIC) column was used with gradient elution. The mobile phase consisted of 0.1% (v/v) aqueous formic acid with 10 mM ammonium formate and acetonitrile with 0.1% (v/v) formic acid. Since riboflavin is an endogenous compound, 4% bovine serum albumin in phosphate buffered saline was used as a surrogate matrix to prepare the calibration curve. The quantification limit for riboflavin in the Beagle dog plasma was 5 ng/mL. The method was fully validated for its specificity, sensitivity, accuracy and precision, recovery, and stability according to the US FDA guidance. The developed LC-MS/MS method may be useful for the in vivo pharmacokinetic studies of riboflavin.

Selective Adsorption of Flavonoids Compounds from the Leaf of Ginkgo biloba L. (은행(Ginkgo biloba L)의 잎으로부터의 Flavonoids 화합물의 선택적 흡착)

  • 윤성용;최원재박종문
    • KSBB Journal
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    • v.11 no.6
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    • pp.726-732
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    • 1996
  • Selective adsorption of plant metabolites from a polar dilute solution onto a polycarboxyl ester sorbent (XAD-7) was investigated. Experimental results demonstrated that neutral resins could selectively concentrate specific flavonoids from dilute aqueous mixtures. Adsorption was dependent on the pH of medium, dosage of the resins and medium composition. Especially the medium composition was a key factor for the selective adsorption and it was found that the selective adsorption was dependent on specific sorbent-sorbate-medium characteristics. Under the optimum condition, selectivity increased up to 85% and the yield of recovery was approached to 98%. It was also found that XAD-7 adsorbed flavonoids in the order of hydrophobicity.

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INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR THE DETERMINATION OF 237Np IN SPENT NUCLEAR FUEL SAMPLES BY ISOTOPE DILUTION METHOD USING 239Np AS A SPIKE

  • Joe, Kihsoo;Han, Sun-Ho;Song, Byung-Chul;Lee, Chang-Heon;Ha, Yeong-Keong;Song, Kyuseok
    • Nuclear Engineering and Technology
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    • v.45 no.3
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    • pp.415-420
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    • 2013
  • A determination method for $^{237}Np$ in spent nuclear fuel samples was developed using an isotope dilution method with $^{239}Np$ as a spike. In this method, inductively coupled plasma mass spectrometry (ICP-MS) was taken for the $^{237}Np$ instead of the previously used alpha spectrometry. $^{237}Np$ and $^{239}Np$ were measured by ICP-MS and gamma spectrometry, respectively. The recovery yield of $^{237}Np$ in synthetic samples was $95.9{\pm}9.7$% (1S, n=4). The $^{237}Np$ contents in the spent fuel samples were 0.15, 0.25, and $1.06{\mu}g/mgU$ and these values were compared with those from ORIGEN-2 code. A fairly good agreement between the measurements (m) and calculations (c) was obtained, giving ratios (m/c) of 0.93, 1.12 and 1.25 for the three PWR spent fuel samples with burnups of 16.7, 19.0, and 55.9 GWd/MtU, respectively.

Effects of Altering Foot Position on Quadriceps Femoris Activation during Wall Squat Exercises

  • Qiao, Yong-Jun;Kim, Kyu-Ryeong;Kim, Myoung-Kwon
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.1
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    • pp.23-31
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    • 2021
  • PURPOSE: This study was conducted to identify the effects of altering foot position on quadriceps femoris including vastus medialis obliques (VMO), vastus lateralis (VL) and rectus femoris (RF) activation during wall squat exercises. METHODS: All subjects (n = 15) were selected and randomly performed three kinds of wall squats: 1) GWS (General Wall Squat), 2) WSS1/4 (Wall Squat Short 1/4), and 3) WSS1/2 (Wall Squat Short 1/2). Each subject completed all three kinds of wall squatting exercises at three different times and recorded the muscle activity data of vastus medialis obliques, vastus lateralis and rectus femoris. RESULTS: Compared with GWS exercise, VMO and RF muscle activity significantly increased under WSS1/2 exercise (p < .05), while only RF muscle activity significantly increased under WSS1/4 exercise (p < .05). CONCLUSION: The results of the present study indicate that moving the foot toward the wall during wall squats has a positive effect on quadriceps activation. The exercise of wall squat short can not only be used as the lower limb muscle strengthening training for normal people, but also as the recovery training for patellofemoral pain syndrome patients in the rehabilitation stage. Besides, Anterior cruciate ligament patients can also try this exercise according to the advice of doctors and therapists.

Ischemic Preconditioning and Its Relation to Glycogen Depletion (허혈성 전처치와 당원 결핍과의 관계)

  • 장대영;김대중;원경준;조대윤;손동섭;양기민;라봉진;김호덕
    • Journal of Chest Surgery
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    • v.33 no.7
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    • pp.531-540
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    • 2000
  • Baclgrpimd; Recent studies have suggested that the cardioprotective effect of ischemic preconditioning(IP) is closely related to glycogen depletion and attenuation of intracellular acidosis. In the present study, the authors tested this hypothesis by perfusion isolated rabbit hearts with glucose(G) is closely related to glycogen depletion and attenuation of intracellular acidosis. In the present study, the authors tested this hypothesis by perfusion isolated rabbit hearts with glucose(G)-free perfusate. Material and Method; Hearts isolated from New Zealand white rabbits(1.5~2.0 kg body weight) were perfused with Tyrode solution by Langendorff technique. After stabilization of baseline hemodynamics, the hearts were subjected to 45 min global ischemia followed by 120 min reperfusion with IP(IP group, n=13) or without IP(ischemic control group, n=10). IP was induced by single episode of 5 min global ischemia and 10 min reperfusion. In the G-free preconditioned group(n=12), G depletion was induced by perfusionwith G-free Tyrode solution for 5 min and then perfused with G-containing Tyrode solution for 10 min; and 45 min ischemia and 120 min reperfusion. Left ventricular functionincluding developed pressure(LVDP), dP/dt, heart rate, left ventricular end-distolic pressure(LVEDP) and coronary flow (CF) were measured. Myocardial cytosolic and membrane PKC activities were measured by 32P-${\gamma}$-ATP incorporation into PKC-specific peptide and PKC isozymes were analyzed by Western blot with monoclonal antibodies. Infarct size was determined by staining with TTC(tetrazolium salt) and planimetry. Data were analyzed by one-way analysis of variance (ANOVA) and Turkey's post-hoc test. Result ; In comparison with the ischemic control group, IP significantly enhanced functional recovery of the left ventricle; in contrast, functional significantly enhanced functional recovery of the left ventricle; in contrast, functional recovery were not significantly different between the G-free preconditioned and the ischemic control groups. However, the infarct size was significantly reduced by IP or G-free preconditioning(39$\pm$2.7% in the ischemic control, 19$\pm$1.2% in the IP, and 15$\pm$3.9% in the G-free preconditioned, p<0.05). Membrane PKC activities were increased significantly after IP (119%), IP and 45 min ischemia(145%), G-free [recpmdotopmomg (150%), and G-free preconditioning and 45 min ischemia(127%); expression of membrane PKC isozymes, $\alpha$ and $\varepsilon$, tended to be increased after IP or G-free preconditioning. Conclusion; These results suggest that in isolated Langendorff-perfused rabbit heart model, G-free preconditioning (induced by single episode of 5 min G depletion and 10 min repletion) colud not improve post-ischemic contractile dysfunction(after 45-minute global ischemia); however, it has an infarct size-limiting effect.

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The Effectiveness and Safety of Acupuncture for Recovery of Patients with Vertebral Compression Fractures: A Systematic Review and Meta-analysis (척추 압박 골절 환자의 회복에 대한 침 치료의 유효성 및 안전성 평가: 체계적 문헌 고찰과 메타분석)

  • Bae, Ji min;Lee, Myeong su;Choi, Ji won;Yang, Gi young;Kim, Kun hyung
    • Korean Journal of Acupuncture
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    • v.36 no.1
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    • pp.1-18
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    • 2019
  • Objectives : The purpose of this study was to evaluate the effectiveness and safety of acupuncture treatment for recovery of patients with vertebral compression fracture(VCF). Methods : We searched ten English and Chinese and seven Korean database up to April 2018. Randomised controlled trials(RCTs), quasi-RCTs, non-radomised Controlled Trials(CCTs) were eligible. Quasi-RCTs and CCTs were assessed only for safety assessment. Pain and adverse events were primary outcome of this review. Quality of life, dysfunction, patient satisfaction, incidence of new vertebral compression fracture were regarded as secondary outcomes. The risk of bias was assessed by two independent authors using the Cochrane risk of bias tool. Level of evidence was tabulated using the GRADE methods. Results : Of 1656 screened, 15 RCTs, 1 quasi-RCT and 3 CCTs were included. Number of participants per study ranged from 45 to 135. Most of the studies had unclear or high risk of bias and considerable heterogeneity in terms of type of intervention, comparison and time-points for outcome measurement. Compared to usual care alone, acupuncture combined with usual care showed short-term favorable results for pain relief in patients with VCF(5 studies, n=252, MD -1.05 point on a 0 to 10 point scale, 95% CI -1.45 to -0.65, $I^2=74%$). Four studies reported mild and temporary adverse events, and no serious adverse events were reported. One study descriptively reported that acupuncture was effective for improving quality of life without providing numerical outcomes. There were no reports of patient satisfaction and incidence of new VCF. Conclusions : Level of evidence is very low for the effectiveness and safety of acupuncture for pain, harms and other clinical outcomes in patients with VCF. Included studies suffered from incomplete reporting, high or unclear risk of bias and substantial heterogeneity between studies. Future high-quality RCTs are needed to assess whether acupuncture is beneficial for recovery of patients with VCF.

Effect of Kyungohkgo on Aerobic Capacity and Anti-fatigue in High School Soccer Players (경옥고 섭취가 고등학교 축구선수의 운동수행능력 향상 및 피로 회복에 미치는 영향)

  • Kim, Dong-Gun;Park, Won-Hyung;Cha, Yun-Yeop
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.5
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    • pp.934-944
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    • 2011
  • This study was designed to investigate the effects of Kyungohkgo to improve aerobic capacity and eliminate exercise-induced fatigue in high school soccer players. Twenty four subjects were participated and randomly assigned into two groups [KG, Kyungohkgo group (n=12); PG, Placebo control group (n=12)]. Two groups were completed treadmill exercise protocol using graded exercise test at before and after experimental treatment of 4 weeks. The $VO_2$max and endurance time were measured by gas analysis and heart rate (HR) was measured by polar system at pre, post 0, post 5, post 15, post 30 and post 60 minutes. Blood samples were collected to analyze blood components. 1. The $VO_2$max was significant increased in the group of after intake Kyungohkgo compared to the group of after intake placebo (p<.05). 2. The HR was significant decreased in the group of after intake Kyungohkgo compared to the group of after intake placebo during recovery time at post 5 mins(p<.05), 30 mins(p<.01), 60 mins(p<.01). 3. Weight, body mass index, percent body fat, anaerobic threshold, endurance time, blood lactate concentrate, lactate dyhydrogenase, creatine kinase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, other energy sources(total-cholesterol, triglyceride, high density lipoprotein-cholesterol, low density lipoprotein-cholesterol, creatinine) and electrolyte (Na, K, Cl) were shown no significant differences between groups. These results suggested that Kyungohkgo can be used as ergogenic aids to improve aerobic capacity and eliminate exercise-induced fatigue.