• Title/Summary/Keyword: m-k value

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Effects of Nitrogen Supplementation Status on CO2 Biofixation and Biofuel Production of the Promising Microalga Chlorella sp. ABC-001

  • Cho, Jun Muk;Oh, You-Kwan;Park, Won-Kun;Chang, Yong Keun
    • Journal of Microbiology and Biotechnology
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    • 제30권8호
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    • pp.1235-1243
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    • 2020
  • The use of microalgal biomass as feedstock for biofuels has been discussed for decades as it provides a sustainable approach to producing fuels for the future. Nonetheless, its feasibility has not been established yet and various aspects of biomass applications such as CO2 biofixation should also be explored. Therefore, in this study, the CO2 biofixation and lipid/carbohydrate production potential of Chlorella sp. ABC-001 were examined under various nitrogen concentrations. The highest biomass productivity and CO2 biofixation rate of 0.422 g/l/d and 0.683 g/l/d, respectively, were achieved under a nitrogen-rich condition (15 mM nitrate). Carbohydrate content was generally proportional to initial nitrate concentration and showed the highest value of 41.5% with 15 mM. However, lipid content showed an inverse relationship with nitrogen supplementation and showed the highest value of 47.4% with 2.5 mM. In consideration as feedstock for biofuels (bioethanol, biodiesel, and biogas), the sum of carbohydrate and lipid contents were examined and the highest value of 79.6% was achieved under low nitrogen condition (2.5 mM). For lipid-based biofuel production, low nitrogen supplementation should be pursued. However, considering the lower feasibility of biodiesel, pursuing CO2 biofixation and the production of carbohydrate-based fuels under nitrogen-rich condition might be more rational. Thus, nitrogen status as a cultivation strategy must be optimized according to the objective, and this was confirmed with the promising alga Chlorella sp. ABC-001.

Synthesis and Smooth Muscle-Selective Relaxant Activity of a Piperidine Analogue: 1-(4'-Fluorophenacyl)-4-Hydroxy-4-Phenyl-Piperidinium Chloride

  • Taqvi, Syed Intasar Hussain;Ghayur, Muhammad Nabeel;Gilani, Anwarul Hassan;Saify, Zafar Saeed;Aftab, Mohammad Tariq
    • Archives of Pharmacal Research
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    • 제29권1호
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    • pp.34-39
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    • 2006
  • The antispasmodic and vasodilator activities of a newly synthesized piperidine derivative (1-(4'fluorophenacyl)-4-hydroxy-4-phenyl-piperidinium chloride) were studied in vitro. The test compound exhibited a dose-dependent relaxant effect on the spontaneous and $K^+$ (75 mM)-induced contractions of isolated rabbit jejunum with respective $EC_{50}$ values of 0.01 mM(0.01-0.02, 95% CI) and 0.30 mM (0.17-0.56). The $Ca^{++}$ channel blocking (CCB) activity was confirmed when the test compound (0.1-0.2 mM) shifted the $Ca^{++}$ dose-response curves to the right, similar to that produced by verapamil ($0.1-1.0{\mu}M$), a standard CCB. In the isolated rabbit aorta, the test compound showed a dose-dependent vasodilator effect on $K^+$ (75 mM)-induced contractions with an $EC_{50}$ value of 0.08 mM (0.02-0.26) while also suppressed the norepinephrine ($1{\mu}M$) control peak responses with $EC_{50}$ value of 0.08 mM (0.05-0.13, n=5). When tested in Langendorff perfused rabbit heart preparation, the test compound exhibited a negligible inhibitory effect on the rate or force of atrial and ventricular contractions when tested up to 5 mM. The results show smooth muscle-selective relaxant effect of the test compound on intestinal and vascular preparations mediated possibly via blockade of voltage and receptor-operated $Ca^{++}$ channels.

암환아 가족의 가족 가치관 분석 (Analysis on Family Value of the Family with Cancer Children)

  • 박인숙;김달숙
    • Child Health Nursing Research
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    • 제7권3호
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    • pp.322-341
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    • 2001
  • The family value is expected to play a crucial role in adjusting a new environment for the family, especially in the critical situation as having a child with cancer in the family. The purpose of the study was to analyze the family values of the family with cancer children in order to offer descriptive data, which will facilitate family adjustment with cancer children. The survey was conducted from July 18, 2000 to August 30, 2000 and the analysis included 309 parents of the children who have been diagnosed as cancer, 18 years of age or less, and treated either hospitalized or at the outpatient clinics. Two instruments were used to measure family value. The modified form of General family value scale was 18 items with a 5 points of Likert response format (Cronbach alpha= .78) and Family value scale was developed for the study with 12 items on a 5 points of Likert response format(Cronbach alpha= .73). The data analysis utilized SAS 6.12 for percentage, frequency, Mean, and t-test of demographic characteristics and mean, F score, ANOVA, and Duncan follow-up test of variable relationships. The study findings were as follows. 1) In General family value, the fathers gave the higher scores to 'The children should live with their parents'(M=4.01), and 'A parents and their children are like one body' (M=3.91). The item with lowest score was 'Its not impossible for man to have extramarital relationship'(M=1.92). The mothers thought the most important items were 'A parents and their children are like one body'(M=3.79), and 'A wife needs to be patient to keep harmony of the family' (M=3.56), and the item with lowest score was 'Its not impossible for man to have extramarital relationship'(M=1.44). 2) The mean scores of the mothers were higher than the fathers for all items in family value with cancer children, while fathers gave more points for items in general family value. Both of parents gave the highest score to 'The health of the family is most important to me'(M=4.85 for fathers, M=4.97 for mothers), and followed by 'The husband and wife need to be patient and understand each other to overcome the difficulties'. The item with lowest scores was 'The parents can have conflicts in making decisions since their child was sick'(M=3.34 for fathers, M=3.37 for mothers). 3) There were significant differences between fathers and mothers in items of General family value; fathers gave more points to the items of 'The children should live with their parents', 'Its essential to hold the ceremony to respect their forefathers', 'Its not impossible for man to have extramarital relationship', 'A woman with two daughters should have one more baby to succeed the generation', 'The husbands are responsible for the household economy', and 'When his mother and wife dont get along, the man should be on his mothers side'. However, there was no significant difference between fathers and mothers in items of Family value with cancer children. 4) The general family value was significantly different by the birth order of cancer children, mothers age, mothers education level, and types of payment. On the other hand, the family value with cancer children was significantly different by the age of cancer children, period of illness, period after completing treatment, family type, the number of family members, and the number of total children.

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Influence of Word of Mouse and Consumers Attitudes on Consumers' Decision-Making in E-Commerce

  • GUO, Chen;KIM, Hyunsu;KIM, Woohyoung
    • 산경연구논집
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    • 제11권8호
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    • pp.7-19
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    • 2020
  • Purpose: Prior studies rarely investigated the effects of the Word of Mouse (WoM) information on consumers' motivation and willingness to purchase a product. Furthermore, few scholars have studied how word-of-mouth information works and they fail to find consistent results. Research design, data and methodology: This study uses a multivariate regression model to investigate the influence of WoM on consumer attitudes and consumer decision-making. It categorizes the quality of WoM into source level and acceptance level, to analyze its influence from a new perspective. A total of 400 surveys were completed, resulting in 336 usable questionnaires for analysis. It was collected in 14 cities from all regions in China. This study constructs a theoretical model of WoM influence on consumers' purchase willingness based on a systematic review of the related literature on WoM quality, perceived value, customer trust, and consumers' purchase willingness. Results: Empirical results reveal that the Internet WoM (consumer's source level and acceptance level) indirectly affects consumer behavior by influencing consumer attitudes. Conclusions: This study provides practical significance and value for merchants to develop better WoM marketing and to establish the reliability of WoM websites. Companies should consider online WoM from the perspective of consumers, thereby improving existing marketing strategies.

Interaction of Antihistaminics with Muscarinic Receptor (III) - Relationship between binding and functional in vitro data -

  • Lee, Shin-Woong;Park, Young-Joo
    • Archives of Pharmacal Research
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    • 제14권2호
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    • pp.181-187
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    • 1991
  • The muscarinic antagonist 1-[benzilic 4, 4'-$[^3H]$ QUINUCLIDINYL BENZILATE $([^3H]$ QNB) bound to a single class of muscarinic receptors with high affinity in rabbit ileal membranes. The $K_D\;and\;B_{ max}$ values for $([^3H]$ QNB calculated from analysis of saturation isotherms were 52.5 pM AND 154 fmol/mg, respectively. Chlopheniramine (CHP), histamine $H_1$ blocker, increased $K_D$ vlue for $([^3H]$QNB without affecting the binding site concentrations and Hill coefficient. The $K_i$ value of CHP for inhibition of $([^3H]$QNB binding in ileal membranes was 1.44\mu{M}$ and the pseudo-Hill coefficient for CHP was close to unit. In the functional assay carbachol, muscarinic agonist, increased the contractile force of ileum with $ED_{50}$ value of $0.11\mu{M}$. CHP caused the rightward shift of the dose-response curve to carbachol. The $pA_2$ value of CHP determined from Schild analysis of carbacholinduced contraction was 5.77 and the slope was unity indicating competitive antagonism with carbachol. The dissociation constant $(K_i)$ of CHP obtained in competitive experiments with $([^3H]$ QNB was similar to the $K_A$ value (1.69 \mu{M)}$ of CHP as inhibitor of carbachol induced contraction in rabbit ileum. This result suggest that the binding of $H_i$ blocker. CHP, vs $([^3H]$QNB to muscarinic receptors in ileal membranes represents an interaction with a receptor of physiological relevance.

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마이크로 웨이브 소결 과정이 CAD/CAM 지르코니아 코아의 적합도에 미치는 영향 (The Influence of Microwave Sintering Process on the Adaptation of CAD/CAM Zirconia Core)

  • 김근배;김지환;이근우
    • 구강회복응용과학지
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    • 제25권2호
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    • pp.95-107
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    • 2009
  • 본 연구의 목적은 전통적인 소결 방법과 마이크로 웨이브 소결 방법에 의해 제작된 지르코니아 코아의 내부 및 변연 적합도를 알아보는 것이다. 본 실험은 기존의 소결로를 이용하는 $3M^{(R)}$의 Lava(LAV), $Kavo^{(R)}$사의 Everest(EVE), $Cerasys^{(R)}$ CAD/CAM 시스템(CER)과 마이크로웨이브 소결로를 이용하는 Dent. $solution^{(R)}$사의 CAD/CAM 시스템(DEN)에서 시스템별로 12개씩의 코아를 제작하고 실리콘 접착제를 이용하여 금속 다이에 부착시켰다. $Skyscan^{(R)}$ 1076 미세 단층 촬영기를 이용해 각각의 시편을 촬영한 후 재구성하였다. 각 시편에 대해 B-L상, M-D상 절단면 및 치아 장축에 대한 횡단면을 구해내고 각각의 단면에 대해 변연 간격, 축면 간격, 교합면 간격을 측정하였다. 실험에 대한 결과는 다음과 같다. 1. 변연 간격은 EVE가 $36.20{\mu}m$로 가장 작았고, LAV는 $47.67{\mu}m$, DEN는 $52.47{\mu}m$, CER은 $54.63{\mu}m$를 나타내었다. 2. 축면 간격은 EVE가 $63.49{\mu}m$로 가장 큰 값을 나타내었으나 네군간에는 유의차는 없었다. 3. 교합면 간격은 DEN이 $77.06{\mu}m$으로 가장 작은 값을 나타내었으며, EVE와 CER은 $100{\mu}m$를 넘는 값으로 다른 두군과 유의차를 보였다. 본 연구에서 마이크로웨이브 소결을 통해 제작된 CAD/CAM 지르코니아 코아는 임상적으로 허용할 만한 변연 간격 및 축면 간격, 교합면 간격을 보여 주었다.

나무 종류에 따른 공기중 분진 농도와 입경 분포에 관한 연구 (Air concentration and particle size distribution of wood dust during wood-working processes)

  • 김승기;노재훈;김치년
    • 한국산업보건학회지
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    • 제9권2호
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    • pp.145-157
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    • 1999
  • Wood dust is created when machines are used to cut or shape wood materials. Industries of high risk of wood dust exposure are sawmills, dimension mills, furniture industries, and carpenters, etc. Health effects associated with wood dust exposure includes dermatitis, allergic respiratory effects and cancer. Health effects of wood dus t are mainly depend on the concentration, dust size and exposure time. This study were carried out to evaluate the concentration and particle size distribution of wood dust during working processes. The subjects of this study were 53 workers exposed to wood dust in 7 furniture factories and 5 musical instruments, and 5 sawmill factories. The average total wood dust concentrations measured by personal cascade impactor were $1.82{\pm}2.31mg/m^3$ in primary manufacture, $3.59{\pm}1.72mg/m^3$ in s econdary manufacture, $5.09{\pm}1.46mg/m^3$ in sanding operation. Mass median diameters of hardwoods dust were $3.36{\mu}m$ in primary manufacture, $4.25{\mu}m$ in secondary manufacture, $4.21{\mu}m$ in sanding operation. softwoods dust were $3.39{\mu}m$ in primary manufacture, $4.34{\mu}m$ in secondary manufacture. Particle size distributions showed a nearly the same pattern in each working processes. The sample concentration of all hardwood dust exceeded the Threshold Limit Value(TLV) and 20.8% of the softwood dust exceeded the Threshold Limit Value. The range of size distribution were $0.5-10{\mu}m$ in the soft and hardwood dust. The respirable dust of soft and hardwood took up 59% and above. Therefore new threshold limit value for wood dust should be needed in Korea. Also, it should be done for various studies on health effects related to occupational exposure of wood dust.

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붕산수용액에서 10B(n·α)7Li 핵반응에 의해 생성된 Li 정량 (Determination of Li generated from 10B(n·α)7Li reaction in Boric acid solution)

  • 최계천;정용주;연제원;김원호
    • 분석과학
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    • 제16권6호
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    • pp.443-449
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    • 2003
  • 붕산수에 대한 열중성자 (thermal neutron) 조사실험을 하나로를 이용하여 다음과 같은 세가지 조건에서 수행하였다: (A) $^{10}B$ 농도 = $203.0{\mu}g/mL$, 조사시간 = 1 시간; (B) $^{10}B$ 농도 = $381.4{\mu}g/mL$, 조사시간 = 1 시간; (C) $^{10}B$ 농도 = $381.4{\mu}g/mL$, 조사시간 = 0.5 시간. 열중성자 조사 시 발생하는 핵반응 [$^{10}B(n{\cdot}{\alpha})^7Li$]으로부터 생성된 $^7Li$의 양은 불꽃 없는 원자흡수분광분석법 (flameless atomic absorption spectroscopy)으로 측정하였다. (A), (B), (C) 실험에서 측정된 $^7Li$의 농도는 각각 0.18 (이론치 = 0.23), 0.31 (이론치 = 0.44), 0.16 (이론치 = 0.22) ${\mu}g/mL$로 이 값들은 각각 이론치의 78.3, 70.5, 71.6%에 해당한다 중성자 조사 후 붕산수의 pH는 조사 전의 값에 비하여 상당히 낮은 값을 보였다. 이는 물의 방사분해물의 영향으로 붕산수가 해리도가 큰 polyborate 형태로 전이되기 때문으로 판단된다.

변형된 복약확인 치료(mDOT) 수행 후의 균음전율에 대한 연구 부제: 보건소 균양성 폐결핵 환자를 대상으로 (Sputum Smear Conversion During mDOT (Modified Directly Observed Treatment))

  • 황택근;김순덕;유세화;신유철
    • Tuberculosis and Respiratory Diseases
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    • 제56권5호
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    • pp.485-494
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    • 2004
  • 연구배경 : DOT를 보건소에서 현실적으로 실행 가능하게 변형시킨 mDOT는, 환자가 꾸준하게 약을 복용하도록 하기 위해 집중치료기간(투약 후 2개월)동안 1주에 1회씩 환자와 의료인 또는 의료보조요원이 면담하여 투약 및 복약감독, 상담 등을 수행하는 일주일 간격의 복약확인 치료법을 의미한다. 이를 균양성 폐결핵 환자들에게 적용시킨 후, 이 mDOT군의 균음전율(sputum smear conversion)을 self군의 그것과 비교하여, mDOT의 수행이 균양성 폐결핵 환자에서의 균음전율에 미치는 효과를 알아보기 위함이다. 방 법 : 서울시 S보건소에서 2001년 10월 8일부터 2002년 4월 23일까지 등록된 균양성환자 52명중에서 24명은 mDOT군, 28명은 자가복용(self)군으로 분류하였다. 24명의 mDOT군중 조절 안 되는 당뇨 동반환자 2명, 외국인 1명, 기타 1명을 제외된 20명의 mDOT군을 선정한 후, 성별, 폐결핵의 범위, 재발유무, 연령을 짝짓기 변수로 해서 일대일 1:1 짝짓기를 실시한 20명의 self군을 선정하여 균음전율을 비교연구 하였다. 본 연구의 경우 mDOT라는 중재만이 있고 무작위추출과 이중맹검이 없기 때문에 일종의 quasi-experimental study라고 할 수 있다. 분석방법은 SAS version 8.1을 이용해 짝지어진 자료에 대한 McNemar test를 사용하였다. 결 과 : 치료 2주 후, 균음전율은 self군에서 50%, mDOT군에서 78.57%로 mDOT군이 self군에서보다 약간 높았으나 통계적으로 유의한 차이는 없었다(p-value=0.289). 치료 1개월에는 mDOT군의 음전율이 self군보다 높게 나타났으나 통계적으로 유의하지는 않았다(83.33% vs 50%, p-value=0.125). 2개월의 균음전율 역시 self군보다 mDOT군에서 비교적 높은 균음전율을 나타냈으나 표본수가 적어 통계적으로 유의하지는 않았다(Table 5, p-value=0.219). 결 론 : 이번 연구에서 집중치료기간 중에 변형된 복약확인 치료를 mDOT군의 20명 모든 환자에게 수행했으며, 앞으로 sample size가 충분히 모아진 연구가 이뤄지면 mDOT가 균양성 폐결핵 환자의 전염성기간(배균기간)을 통계적으로 유의하게 단축시킬 수 있다는 방향성을 제시한데에 의미가 있다. 우리나라에서 복약확인치료(DOT)는 폐결핵 환자의 치료에 효과적일 수 있고, 어떤 고위험군에서 유용하리라 생각된다. 앞으로 좀 더 큰 규모의 전향적(prospective) 연구가 필요한 것으로 사료된다.