• Title/Summary/Keyword: Mass changes

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Sedimentary Excess Barium from a Core of the Northwest Pacific Ocean: Geochemical Proxy

  • Suk, Bong-Chool;Park, Chan-Hong;Taira, Asahiko;Hyun, Sang-Min
    • Journal of the korean society of oceanography
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    • v.35 no.2
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    • pp.98-108
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    • 2000
  • A geochemical study on a hemipelagic core sediment taken from the northwest Pacific Ocean (eastern edge of the Shikoku Basin) was conducted to use of excess barium (Ba(ex)) for evaluate the paleoceano-graphic changes. Also, the excursion of sedimentary Ba(ex) was compared with those of biogenic opal, carbonate and organic carbon content in the sediment during the last glacial and interglacial periods. The calculated Ba(ex) derived from the major and minor element shows a distinctive glacial-interglacial variations, and the mass accumulation rate (MAR) of Ba(ex) shows coincident variations with the MARs of biogenic fractions. Especially, strong positive correlation (r$^2$=0.85) between the MAR of Ba(ex) and the MAR of biogenic carbonate is recognized. Based on the strong positive correlation(r$^2$=0.85) between the MAR of Ba(ex) and the MAR of carbonate content, we estimated the degree of carbonate dissolution rate during the glacial and interglacial periods. Assuming the proportional variation and the refractory nature of barium exist between two factors, the variation of index Ca/Ba ratio in sediment indicates the degree of carbonate dissolution. Sedimentary Ca/Ba ratios index clearly show a striking fluctuation between the glacial and interglacial periods with higher positive correlation during glacial and lower correlation during interglacial. This fact indicates enhanced carbonate dissolution during interglacial period. Thus, the sedimentary Ca/Ba ratio in sedimentary records can be used as one of the useful tools for estimation of the relative degree of carbonate dissolution. The excursion of Ba(ex) and the sedimentary Ca/Ba ratio follows the typical pacific carbonate dissolution type(enhanced dissolution during interglacial and reduced dissolution during glacial time) as suggested by previous work (e.g., Wu et al., 1990). Variation in sedimentary Ca/Ba ratio thus strongly supports that glacial-interglacial fluctuation in carbonate dissolution has been prevailed in the northwest Pacific Ocean.

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Evaluation of Luminescent P450 Analysis for Directed Evolution of Human CYP4A11

  • Choi, Seunghye;Han, Songhee;Lee, Hwayoun;Chun, Young-Jin;Kim, Donghak
    • Biomolecules & Therapeutics
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    • v.21 no.6
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    • pp.487-492
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    • 2013
  • Cytochrome P450 4A11 (CYP4A11) is a fatty acid hydroxylase enzyme expressed in human liver. It catalyzes not only the hydroxylation of saturated and unsaturated fatty acids, but the conversion of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), a regulator of blood pressure. In this study, we performed a directed evolution analysis of CYP4A11 using the luminogenic assay system. A random mutant library of CYP4A11, in which mutations were made throughout the entire coding region, was screened with luciferase activity to detect the demethylation of luciferin-4A (2-[6-methoxyquinolin-2-yl]-4,5-dihydrothiazole-4-carboxylic acid) of CYP4A11 mutants in Escherichia coli. Consecutive rounds of random mutagenesis and screening yielded three improved CYP4A11 mutants, CP2600 (A24T/T263A), CP2601 (T263A), and CP2616 (A24T/T263A/V430E) with ~3-fold increase in whole cells and >10-fold increase in purified proteins on the luminescence assay. However, the steady state kinetic analysis for lauric acid hydroxylation showed the significant reductions in enzymatic activities in all three mutants. A mutant, CP2600, showed a 51% decrease in catalytic efficiency ($k_{cat}/K_m$) for lauric acid hydroxylation mainly due to an increase in $K_m$. CP2601 and CP2616 showed much greater reductions (>75%) in the catalytic efficiency due to both a decrease in $k_{cat}$ and an increase in Km. These decreased catalytic activities of CP2601 and CP2616 can be partially attributed to the changes in substrate affinities. These results suggest that the enzymatic activities of CYP4A11 mutants selected from directed evolution using a luminogenic P450 substrate may not demonstrate a direct correlation with the hydroxylation activities of lauric acid.

Effects of Counter-rotation Position on Knee/Hip Angulation, Center of Mass Inclination, and Edging Angle in Simulated Alpine Skiing

  • Yoon, Sukhoon;Kim, Jin-Hae;Park, Jae-Hyeon;Ryu, Jiseon;Park, Sang-Kyoon;Kim, Joo-Nyeon
    • Korean Journal of Applied Biomechanics
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    • v.27 no.2
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    • pp.91-97
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    • 2017
  • Objective: To investigate rotation movement of segment for performing each position and its effect on knee/hip angulation, COM inclination, and edging angle changes. Method: Twelve Alpine skiers (age: $25.8{\pm}4.8years$, height: $173.8{\pm}5.9cm$, weight: $71.4{\pm}7.4kg$, length of career: $9.9{\pm}4.6years$) participated in this study. Each skier was asked to perform counter-rotation, neutral, and rotation positions. Results: Shank and thigh were less rotated in the counter-rotation position than in other positions, whereas the trunk and pelvis were more counter-rotated (p<.05). Hip angulation, COM inclination, and edging angle were significantly greater in the counter-rotation position than in other positions (p<.05). Conclusion: Our finding proved that the counter-rotation position increases hip angulation, COM inclination, and edging angle. Consequently, we suggest that skiers should perform counter-rotation of the trunk and pelvis relative to the ski direction in the vertical axis for the counter-rotation position. Further analysis will continue to investigate the effects of the counter-rotation position in real ski slope with kinetic analysis.

Spin evolution of Horizon-AGN early-type galaxies

  • Choi, Hoseung;Yi, Sukyoung K.;Dubois, Yohan;Kimm, Taysun;Devriendt, Julien. E.G.;Pichon, Christophe
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.33.1-33.1
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    • 2018
  • The differential rotational properties of early-type galaxies (ETGs) revealed by integral field spectroscopy surveys is arguably one of the most exciting findings in the galaxy evolution study during the past decade. Numerical studies have shown that galaxy mergers under various configurations can reproduce the observed distribution of ETG spin. However, we suggest an alternative scenario for the spin evolution of a large fraction of ETGs. Using the Horizon-AGN simulation, we follow the spin evolution of 10037 color-selected ETGs more massive than 1010 Msun that are divided into four groups: cluster centrals (3%), cluster satellites (33%), group centrals(5%), and field ETGs (59%). We find a strong mass dependence of the slow rotator fraction, fSR, and the mean spin of massive ETGs. Although the environmental dependence is not clear in the fSR, it is visible in the mean value of the spin parameter. The environmental dependence is driven by the satellite ETGs whose spin gradually decreases as their environment becomes denser. Galaxy mergers appear to be the main cause of total spin changes in 94% of central ETGs of halos with Mvir > 1012.5 Msun, but only 22% of satellite and field ETGs. We find that non-merger induced tidal perturbations better correlate with the galaxy spin-down in satellite ETGs than mergers. Given that the majority of ETGs are not central in dense environments, we conclude that non-merger tidal perturbation effects played a key role in the spin evolution of ETGs observed in the local (z < 1) universe.

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Comparison of Appropriate Piperacillin/Tazobactam Doses in Korean Obese Patients with Cancer Based on Different Body Size Descriptor Equations in a Tertiary Care Hospital (국내 3차 병원의 비만 암환자에서 각각 다른 체중 측정 공식들을 적용한 piperacillin/tazobactam의 용량 적절성 비교 연구)

  • Kim, Ji Hyun;Yang, Young-Mo;Yoon, Hyonok;Choi, Eun Joo
    • Korean Journal of Clinical Pharmacy
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    • v.27 no.2
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    • pp.83-91
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    • 2017
  • Background: Piperacillin/tazobactam (TZP) is an antibiotic against a broad spectrum of gram-positive, gram-negative, and aerobic and anaerobic strains of bacteria. Due to changes in its pharmacokinetic and pharmacodynamic parameters by TZP-treated patients' renal functions and obesity, it is important to administrate and monitor TZP based on their renal functions and Body Mass Index (BMI) levels. The purpose of this study was to determine the appropriateness of administration doses of TZP based on renal functions of obese cancer patients in a tertiary hospital. Methods: This study was retrospectively conducted with obese cancer patients with $BMI{\geq}30kg/m^2$ in a tertiary hospital, Korea from September 2004 to August 2014. Data were collected through Electronic Medical Record (EMR) which contained laboratory data and TZP dosing of each patient. Results: Among 7,058 patients during the study period, 102 prescriptions were selected based on inclusion and exclusion criteria and classified by their renal functions. Although TZP should be used based on patients' renal functions to adjust its dose, its initial dose and dosing interval were consistently used without considering patients' renal functions on a regular basis. Especially, in the comparison with FDA dosing standard of TZP, approximately twice patients with $20mL/min{\leq}CrCl{\leq}40mL/min$ received domestically 4.5 g instead of 2.25 g as the TZP starting dose. Conclusion: The appropriate doses of TZP were administered to almost all of obese cancer patients; however, the recommended TZP dose was different between Korea and other countries by twice the amount. Further related studies are necessary to clearly determine the results, to optimize TZP treatment for obese patients with cancer in clinical practice, and to design and develop new TZP formulations for them in pharmaceutical industry.

How Digital Camera Has Changed Photographers? A Phenomenological Approach of Digital Labor (디지털 사진 이후 사진가들의 변화 현상학적 접근을 중심으로)

  • Cho, In Won
    • Korean journal of communication and information
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    • v.84
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    • pp.124-151
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    • 2017
  • This study examines photographers who experienced steep changes from film to digital photography working and photography culture after using digital camera through a phenomenological approach. Digital technologies have brought many transition. Most of all digital camera popularize photography among people who had no knowledge and experience about camera. On the contrary digital photography made many professional photographers difficulties. After being digital photography, most film companies and film developing and printing studios have diminished. In addition many professional photographers have to cover increasing working time by decreasing photography price. For this research researcher interviewed 12 professional photographers who is working as a digital photographer. After collecting data, researcher analyse data by phenomenological approach. This study is looking for a meaning of photographers' labor after digital photography times.

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Equipment for Measuring the Adiabatic Temperature Rise of Concrete by Compensating Heat Loss (열손실량 보정을 통한 콘크리트 단열온도상승량 예측 장치)

  • Jin, Eun-Woong;Kim, Chin-Yong;Kim, Jin-Keun
    • Journal of the Korea Concrete Institute
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    • v.24 no.5
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    • pp.535-542
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    • 2012
  • Adiabatic temperature rise test for predicting heat of hydration in mass concrete is especially inconvenient in the field. In order to overcome the problem, the equipment to effectively and conveniently measure semi-adiabatic temperature change was developed. The main objective of this paper is to propose a new and simple equipment for measuring semi-adiabatic temperature rise by using insulation bottles. In order to predict exact heat loss of concrete using this device, it is required to assume the specific heat loss coefficient of the device by water temperature change inside the experimental device. According to experimental and analytical results, the adiabatic temperature rise does not have significant differences in changes of temperature and humidity of air, as well as initial temperature of water. By comparing adiabatic temperature rise tests, the equipment for measuring semi-adiabatic temperature change can be used to predict the hydration heat of concrete within sufficient accuracy.

A Neuropathic Atypical Odontalgia Recognized after the Apicoectomy under Local Anesthesia on the Maxillary Lateral Incisor -A Case Report- (국소마취하 상악 측절치 치근단 절제술 후 인식된 신경병성 비정형 치통 1예 -증례 보고-)

  • Mo, Dong-Yub;Yoo, Jae-Ha;Choi, Byung-Ho;Kim, Ha-Rang;Lee, Chun-Ui;Kim, Jong-Bae
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.10 no.1
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    • pp.20-26
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    • 2010
  • This type of neuropathic pain(atypical odontalgia) is seen most often in middle-aged women or men after dentoalveolar operation. Atypical odontalgia probably is caused by deafferentation leading to intraneural changes in the medullary dorsal horn. Treatment of this problem is difficult, but some success has been reported in uncontrolled, open-labeled studies using high doses of tricyclic antidepressants. This is the management report of a patient case, that had a neuropathic atypical odontalgia recognized with the right maxillary lateral incisor. The patient was consulted to the Department of Pain Clinics, ENT & Neurology and diagnosed the adenoid cystic carcinoma on left cerebellum and right paranasal sinus with extension to the cavernous sinus. In spite of the osteoplastic craniotomy, neurosurgical mass removal and radiation therapy were done with chemotherapy, atypical odontalgia was continued. In addition to the consultation to Psychology, stress management and antidepressant medication were done and improved slowly.

Hydraulic Behaviors of KSTAR PF Coils in Operation

  • Park, S.H.;Chu, Y.;Kim, Y.O.;Yonekawa, H.;Chang, Y.B.;Woo, I.S.;Lee, H.J.;Park, K.R.
    • Progress in Superconductivity and Cryogenics
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    • v.14 no.2
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    • pp.24-27
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    • 2012
  • The superconducting coil system is one of the most important components in Korea Superconducting Tokamak Advanced Research (KSTAR), which has been operated since 2008. $Nb_3Sn$ and NbTi superconductors are being used for cable-in-conduit conductors (CICCs) of the KSTAR toroidal field (TF) and poloidal field (PF) coils. The CICCs are cooled by forced-flow supercritical helium about 4.5 K. The temperature, pressure and mass flow rate of the supercritical helium in the CICCs are interacting with each other during the operation of the coils. The complicate behaviors of the supercritical helium have an effect on the operation and the efficiency of the helium refrigeration system (HRS) by means of, for instance, pressure drop. The hydraulic characteristics of the supercritical helium have been monitored while the TF coils have stably achieved the full current of 35 kA. In other hands, the PF coils have been operated with various pulsed or bipolar mode, so the drastic changes happen in view of hydraulics. The heat load including AC loss on the coils has been analyzed according to the measurement. These activities are important to estimate the temperature margin in various PF operation conditions. In this paper, the latest hydraulic behaviors of PF coils during KSTAR operation are presented.

Development of Health Information Program for the Middle Aged Women (중년여성을 위한 건강정보 프로그램 개발과 건강교육 활용에 관한 연구)

  • Park, Hyeoun-Ae;Park, Young-Sook;Oh, Hyo-Sook;Kim, Hoo-Jung
    • Women's Health Nursing
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    • v.8 no.2
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    • pp.165-176
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    • 2002
  • The purpose of the study was to develop a Web site for the middle-aged women and test the usability of the site. Users' need for information were identified via online survey of 189 middle-aged women. It was found that they had various health problems but very few did any health prevention or health promotion activities. A web site for the middle-aged women was developed based on the result of needs assessment. The site includes content on exercise, diet including weight control, osteoporosis, climacteric, aging, breast and cervical cancer. Besides this health information, FAQ on women's health, my health knowledge test, statistics, link to related institutes and web sites, newspaper articles/mass media clips, journal articles, conferences, papers and other educational information were added. The site was developed as a subsystem of the Healthguide(http://healthguide.kihasa.re.kr). As a way of utilizing the homepage, twenty two women aged 40-50 were recruited at a community-based gathering and health promotion education program was conducted. To test the effectiveness of the education, knowledge, attitude and behavior changes of before and after education were compared. There were significant differences of knowledge and behavior in breast cancer, cervical cancer, osteoporosis, menopause and sexual life. It is expected that Web-based women's health information will contribute to women's health promotion and provide an effective learning media for health education.

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