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Changes in Moisture Contents of Rice-hull Based Root Media and Growth Responses of 'Seolhyang' Strawberry during Vegetative Propagation (육묘 과정 중 포트에 충진된 팽연왕겨 혼합상토의 함수량 변화와 '설향' 딸기의 생장 반응)

  • Park, Gab Soon;Kim, Yeoung Chil;Ann, Seoung Won;Kang, Hee Kyoung;Choi, Jong Myung
    • Horticultural Science & Technology
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    • v.33 no.1
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    • pp.47-54
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    • 2015
  • This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

A Mid-late Maturing Rice Cultivar with High-Quality and Bacterial Blight Resistance "Jinbaek" (벼 중만생 고품질 흰잎마름병 신균계(K3a) 저항성 품종 "진백")

  • Kim, Ki-Young;Shin, Mun-Sik;Kim, Bo-Kyeong;Ko, Jae-Kwon;Noh, Tae-Hwan;Ha, Ki-Yong;Ko, Jong-Cheol;Kim, Woo-Jae;Nam, Jeong-Kwon;Baek, Man-Gee;Noh, Gwang-Il;Park, Hyun-Su;Baek, So-Hyeon;Shin, Woon-Chul;Mo, Young-Jun;Choung, Jin-Il;Kim, Young-Doo;Kang, Hyun-Jung;Kim, Chung-Kon;Hwang, Hung-Goo;Kim, Je-Kyu
    • Korean Journal of Breeding Science
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    • v.41 no.3
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    • pp.314-318
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    • 2009
  • A new rice cultivar "Jinbaek" carrying Xa3 and xa5 was derived from the cross between 'HR15204-38-3' with xa5 gene resistant to bacterial blight K1, K2, K3 and K3a, and F1 plant derived from the cross between Junam and Sindongjin with Xa3 gene. "Jinbaek" has approximately 125 days of growth duration from transplanting to harvesting in the west-southern coastal and Honam plain of Korea. Culm length of "Jinbaek" is 71 cm. In reaction to biotic stresses, it shows moderate resistance to blast, and wide spectrum resistance to bacterial blight pathogen, K1, K2, K3, and K3a but susceptible to rice stripe virus and blast. The milled rice of "Jinbaek" exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has lower amylose content (18.8%) and protein content (6.2%) compared with Nampyeong. The milled rice yield of this cultivar was 5.30 MT/ha in local adaptability test of three years from 2006 to 2008. This cultivar would be adaptable to the bacterial blight-prone area in the south-western coast and Honam plain of Korea.

A High Essential Amino Acid Properties Rice Cultivar 'Haiami' (필수아미노산 고함유 신품종 '하이아미')

  • Hong, Ha-Cheol;Kim, Yeon-Gyu;Yang, Chang-Ihn;Hwang, Hung-Goo;Lee, Jeom-Ho;Lee, Sang-Bok;Choi, Yong-Hwan;Kim, Hong-Yeol;Lee, Kyu-Seong;Yang, Sae-Jun;Kim, Myeong-Ki;Jeong, O-Young;Cho, Young-Chan;Jeon, Yong-Hee;Choi, Im-Soo;Jeong, Eung-Gi;Oh, Sea-Kwan;O, Myeong-Gyu;Yea, Jong-Du;Shin, Young-Seoup;Kim, Jeong-Ju
    • Korean Journal of Breeding Science
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    • v.43 no.6
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    • pp.543-548
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    • 2011
  • Haiami is a new Japonica rice variety developed from a cross between 'Jinmibyeo' TR treated with ethyl methane sulfonate (EMS) EMS and 5-methytryptophan, and 'Gyehwabyeo' in order to develop a new premium quality rice variety by a rice breeding team of National Institute of Crop Science, Rural Development Administration in 2008. This variety has about 138 days of growth duration from transplanting to harvesting in central plain area of Korea. The heading date of this vareity was on $15^{th}$, August. The 'Haiami' has good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Haiami' is more than that of 'Hwaseongbyeo'. This variety shows slow leaf senescence and considerable tolerance to viviparous germination. It is susceptible to leaf blast, bacterial blight, and insect pests, but resistance to rice stripe virus. The milled rice of this variety exhibited translucent, clear non-glutinous endosperm and short grain shape. The essential amino acid properties of 'Haiami' have more than 31% that of 'Hwaseongbyeo' in polished rice. This variety has premium palatability of cooked rice. The yield performance of this rice cultivar was about 5.38 MT/ha in milled rice in local adaptability test for three years from 2006 to 2008. 'Haiami' is adaptable to central and southern plain areas of Korea.

Anti-inflammatory Effect of Heat-Killed Enterococcus faecalis, EF-2001 (열처리 사균체 엔테로코커스 패칼리스 EF-2001의 항염증 효과)

  • Choi, Moon-Suk;Chang, Sang-Jin;Chae, Yuri;Lee, Myung-Hun;Kim, Wan-Joong;Iwasa, Masahiro;Han, Kwon-Il;Kim, Wan-Jae;Kim, Tack-Joong
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1361-1368
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    • 2018
  • Inflammation is the most common condition in the human body. Tissue damage triggers inflammation, together with vasodilation and increased blood flow at the inflamed site, resulting in edema. Inflammatory responses are also triggered by lipopolysaccharide (LPS), a Toll-like receptor Enterococcus faecalis, a gram-positive organism, has been reported to possess immunomodulatory and preventive activities; however, its use may present risks of sepsis and other systemic infections. Heat-killed Enterococcus faecalis (EF-2001) has been reported to induce antitumor activity, but its effects on inflammation are not known. In the present study, we investigated the effect of EF-2001 on LPS-induced macrophage inflammatory responses. EF-2001 treatment reduced nitric oxide (NO) production, indicating suppression of inflammatory reactions. EF-2001 showed no cytotoxicity in macrophages. Further investigation of the anti-inflammatory mechanism of EF-2001 indicated that EF-2001 reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2. EF-2001 also reduced f the LPS induction of several inflammatory molecules involved in the nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) and mitogen-activated protein kinase pathways, including ERK, JNK, and p38 phosphorylation, in a concentration-dependent manner. Additionally, EF-2001 inhibited Akt phosphorylation and increased the expression of the inhibitory ${\kappa}B$ ($I{\kappa}B$) protein, an inhibitor of $NF-{\kappa}B$. EF-2001 also inhibited the nuclear translocation of p65. These results suggest that EF-2001 has anti-inflammatory properties and may be useful for treating inflammatory diseases.

Whitening and Antioxidant Effects of Extracts from Angelica gigas Nakai Thin Root (참당귀 세미 추출물의 미백 및 항산화 효과)

  • Lee, Sang-Hoon;Park, Jeong-Yong;Seo, Kyung Hye;Choi, Jang Nam;Lee, Yoon-Jeong;Moon, Youn-Ho;Hur, Mok;Park, Woo Tae;Huh, Yun Chan;Chang, Jae-Ki;Koo, Sung Cheol
    • Korean Journal of Plant Resources
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    • v.34 no.1
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    • pp.37-43
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    • 2021
  • Angelica gigas Nakai (AGN) is a perennial plant belonging to the family Apiaceae. Its root has been utilized as a traditional medicine especially in Korea. This study was carried out to evaluate the potential use of extracts from AGN root parts as a cosmetic material. The dried AGN roots are divided into body (B), thick root (TkR), medium root(MR) and thin root (TnR) according to their diameter before cutting into medicine. B, TkR and MR of AGN are combined and used as medicinal herbs (MH). The extracts from AGN each root part (B, TkR, MR, TnR, MH) were used to test the effect on cell viability using MTS assay and to examine inhibitory effect on melanin accumulation in B16F10 melanoma cells. All extracts (50 - 200 ㎍/mL) from the each root part did not affect the cell viability. And inhibitory effect of all root extracts (200 ㎍/mL) on melanin accumulation was 12-19%. Especially, TnR showed similar inhibitory effect on melanin accumulation to MH. In addition, DPPH and ABTS free radical scavenging activity were higher in the TnR extract compared to MH. This study showed that the TnR extract exhibit high inhibitory effect on melanin accumulation and antioxidant activity compared to MH, suggesting that TnR extract has potential as a cosmetic ingredient.

A Study on the Emotional Happiness of Human (인간의 감성적 행복감에 관한 연구)

  • Jeong, Cheol-Yeong
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.6
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    • pp.211-220
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    • 2019
  • It helps to wisely abstain from errors of the a priori subjective emotions related to human emotions, and orders emotions to make rational choices. These emotional happiness of human and moral sensitivities work directly or indirectly in rational choice of rational thought and reason. Abraham would have been troubled by the divine mandate to sacrifice a son who was only one, and a son who had been healed. Was his reason reasonable at this time? In rational reason, it can be said that the act of dedicating his son is an appropriate act, but is it possible in the human mind? Aristoteles also called human virtue virtue in good for human beings. Because happiness is also a mental activity, we have to know a certain degree about the mind. This ψυχή(psyche, spirit) spirit is an irrational element that is invisible but an intervention in rational principles. Also C. G. Jung states that all human beings have four dynamic psychological functions that are not visible, and that the mind is driven by these four functional dimensions. This means that the elements of S, Sensing, N, Intuition, T, Thinking, and Feeling are combined. David Hume also emphasized the principle of empathy, asserting that morality can not be derived from reason, and Max Ferdinand Scheler, before grasping the visual characteristics of a person, has already captured the whole feeling of the person, And that the value given to this feeling is the value, and that the function of emotion that is elevated to the perceived object by grasping the value through this process and the value is always preceded by the reason. Emmanuel Levinas states that emotional emotions of love are ahead of reason and that emotions precede human reasoning and rationality is the inability of emotional control that we need rational thought and rational and wise action as reason of control and temperance. As part of human emotional education, in the 7th curriculum, Bloom's cognitive, perceptive, and behavioral domain, which is a person with integrated thinking, is trying to be a moral practitioner. It focuses on how to act according to the direction of emotions for virtuous acts and how to develop emotions for emotions on behalf of vicious acts. We can design the possibility and direction of cultivating human emotions and emotional happiness and happy sensitivities by the principle of strengthening virtue and the principle of elimination of ill feeling.

To Assess Whether Lee's Grading System for Central Lumbar Spinal Stenosis Can Be Used as a Decision-Making Tool for Surgical Treatment (요추 중심 신경관 협착에 있어서 Lee's Grade를 통한 MRI 평가방법이 수술적 치료 결정에 유용한가에 대한 연구)

  • Do Yeon Ahn;Hee Jin Park;Jung Woo Yi;Ji Na Kim
    • Journal of the Korean Society of Radiology
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    • v.83 no.1
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    • pp.102-111
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    • 2022
  • Purpose To evaluate the correlation between Lee's grades and surgical intervention for central lumbar spinal stenosis (CLSS) and to assess whether this grading system can be used as a decision-making tool for the surgical treatment of this condition. Materials and Methods This retrospective study included 290 patients (M:F = 156:134; mean age, 46 ± 16 years). Radiologists assessed the presence and grade of CLSS at the stenosis point according to Lee's grading system, in which CLSS is classified into four grades according to the shape of the cauda equina. Correlation coefficients (rs) between Lee's grades and the operation were calculated with Spearman rank correlation. Results Among the operated patients, grade 2 was the most commonly assigned grade (50%-58%), grade 3 was less common (35%), and grade 0 was the least common (2%-3%). Among the non-operated patients, grade 1 was the most common (63%-65%), grade 0 was less common (15%-16%), and grade 3 was the least common (8%). The distribution of grades differed between the operated and non-operated groups (p < 0.001). Less than 25% of patients who underwent surgery were assigned grades 0 and 1, and more than 88% were assigned grades 2 and 3. A moderate correlation was found between the grade and surgical intervention (rs = 0.632 and rs = 0.583). Conclusion Lee's grade was moderately correlated with surgical intervention. Lee's grading system can be a decision-making tool for the surgical treatment of CLSS.

A Study on Startups' Dependence on Business Incubation Centers (창업보육서비스에 따른 입주기업의 창업보육센터 의존도에 관한 연구)

  • Park, JaeSung;Lee, Chul;Kim, JaeJon
    • Korean small business review
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    • v.31 no.2
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    • pp.103-120
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    • 2009
  • As business incubation centers (BICs) have been operating for more than 10 years in Korea, many early stage startups tend to use the services provided by the incubating centers. BICs in Korea have accumulated the knowledge and experience in the past ten years and their services have been considerably improved. The business incubating service has three facets : (1) business infrastructure service, (2) direct service, and (3) indirect service. The mission of BICs is to provide the early stage entrepreneurs with the incubating service in a limited period time to help them grow strong enough to survive the fierce competition after graduating from the incubation. However, the incubating services sometimes fail to foster the independence of new startup companies, and raise the dependence of many companies on BICs. Thus, the dependence on BICs is a very important factor to understand the survival of the incubated startup companies after graduation from BICs. The purpose of this study is to identify the main factors that influence the firm's dependence on BICs and to characterize the relationships among the identified factors. The business incubating service is a core construct of this study. It includes various activities and resources, such as offering the physical facilities, legal service, and connecting them with outside organizations. These services are extensive and take various forms. They are provided by BICs directly or indirectly. Past studies have identified various incubating services and classify them in different ways. Based on the past studies, we classify the business incubating service into three categories as mentioned above : (1) business infrastructure support, (2) direct support, and (3) networking support. The business infrastructure support is to provide the essential resources to start the business, such as physical facilities. The direct support is to offer the business resources available in the BICs, such as human, technical, and administrational resources. Finally, the indirect service was to support the resource in the outside of business incubation center. Dependence is generally defined as the degree to which a client firm needs the resources provided by the service provider in order to achieve its goals. Dependence is generated when a firm recognizes the benefits of interacting with its counterpart. Hence, the more positive outcomes a firm derives from its relationship with the partner, the more dependent on the partner the firm must inevitably become. In business incubating, as a resident firm is incubated in longer period, we can predict that her dependence on BICs would be stronger. In order to foster the independence of the incubated firms, BICs have to be able to manipulate the provision of their services to control the firms' dependence on BICs. Based on the above discussion, the research model for relationships between dependence and its affecting factors was developed. We surveyed the companies residing in BICs to test our research model. The instrument of our study was modified, in part, on the basis of previous relevant studies. For the purposes of testing reliability and validity, preliminary testing was conducted with firms that were residing in BICs and incubated by the BICs in the region of Gwangju and Jeonnam. The questionnaire was modified in accordance with the pre-test feedback. We mailed to all of the firms that had been incubated by the BICs with the help of business incubating managers of each BIC. The survey was conducted over a three week period. Gifts (of approximately ₩10,000 value) were offered to all actively participating respondents. The incubating period was reported by the business incubating managers, and it was transformed using natural logarithms. A total of 180 firms participated in the survey. However, we excluded 4 cases due to a lack of consistency using reversed items in the answers of the companies, and 176 cases were used for the analysis. We acknowledge that 176 samples may not be sufficient to conduct regression analyses with 5 research variables in our study. Each variable was measured through multiple items. We conducted an exploratory factor analysis to assess their unidimensionality. In an effort to test the construct validity of the instruments, a principal component factor analysis was conducted with Varimax rotation. The items correspond well to each singular factor, demonstrating a high degree of convergent validity. As the factor loadings for a variable (or factor) are higher than the factor loadings for the other variables, the instrument's discriminant validity is shown to be clear. Each factor was extracted as expected, which explained 70.97, 66.321, and 52.97 percent, respectively, of the total variance each with eigen values greater than 1.000. The internal consistency reliability of the variables was evaluated by computing Cronbach's alphas. The Cronbach's alpha values of the variables, which ranged from 0.717 to 0.950, were all securely over 0.700, which is satisfactory. The reliability and validity of the research variables are all, therefore, considered acceptable. The effects of dependence were assessed using a regression analysis. The Pearson correlations were calculated for the variables, measured by interval or ratio scales. Potential multicollinearity among the antecedents was evaluated prior to the multiple regression analysis, as some of the variables were significantly correlated with others (e.g., direct service and indirect service). Although several variables show the evidence of significant correlations, their tolerance values range between 0.334 and 0.613, thereby demonstrating that multicollinearity is not a likely threat to the parameter estimates. Checking some basic assumptions for the regression analyses, we decided to conduct multiple regression analyses and moderated regression analyses to test the given hypotheses. The results of the regression analyses indicate that the regression model is significant at p < 0.001 (F = 44.260), and that the predictors of the research model explain 42.6 percent of the total variance. Hypotheses 1, 2, and 3 address the relationships between the dependence of the incubated firms and the business incubating services. Business infrastructure service, direct service, and indirect service are all significantly related with dependence (β = 0.300, p < 0.001; β = 0.230, p < 0.001; β = 0.226, p < 0.001), thus supporting Hypotheses 1, 2, and 3. When the incubating period is the moderator and dependence is the dependent variable, the addition of the interaction terms with the antecedents to the regression equation yielded a significant increase in R2 (F change = 2.789, p < 0.05). In particular, direct service and indirect service exert different effects on dependence. Hence, the results support Hypotheses 5 and 6. This study provides several strategies and specific calls to action for BICs, based on our empirical findings. Business infrastructure service has more effect on the firm's dependence than the other two services. The introduction of an additional high charge rate for a graduated but allowed to stay in the BIC is a basic and legitimate condition for the BIC to control the firm's dependence. We detected the differential effects of direct and indirect services on the firm's dependence. The firms with long incubating period are more sensitive to indirect service positively, and more sensitive to direct service negatively, when assessing their levels of dependence. This implies that BICs must develop a strategy on the basis of a firm's incubating period. Last but not least, it would be valuable to discover other important variables that influence the firm's dependence in the future studies. Moreover, future studies to explain the independence of startup companies in BICs would also be valuable.

The Respiratory and Hemodynamic Effect of Prone Position in Patients with ARDS (급성호흡부전증후군에서 Prone Position의 호흡 및 혈류역학적 효과)

  • Lim, Chae-Man;Koh, Youn-Suck;Jung, Bok-Hyun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1105-1113
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    • 1997
  • Background : Prone position improves oxygenation in some patients with ARDS. According to some authors, prone position can also improve the deteriorated hemodynamics induced by PEEP. But these respiratory and hemodynamic effects of prone position has not yet been fully established. Methods : Twentythree consequtive patients with ARDS(M : F= 11 : 12, $62.1{\pm}20.8yrs$) were the subjects for this study. ABGA, static compliance of the respiratory system, mean arterial pressure and pulse rate were obtained in supine position and at 5min, 0.5h and 2h of prone position. Positive respiratory response was defined as 20mmHg or more increase in $PaO_2/FIO_2$ within 2h of prone position. Early of late respiratory responses were defined if the positive response was observed within of after 3 day of ARDS onset, respectively. Positive hemodynamic response was defined as 10mmHg or more increase in mean arterial pressure at 5min of prone position. Results : Fifteen patients (65%) showed positive respiratory response. In the respiratory responders, $PaO_2$ was $69.8{\pm}17.6mmHg$ in supine position, $83.2{\pm}22.6mmHg$ in prone position 0.5h, $96.8{\pm}22.7mmHg$ in prone position 2h(p<0.001), and $PaO_2/FIO_2$ was $108{\pm}41mmHg$, $137{\pm}57mmHg$, $158{\pm}50mmHg$, respectively(p=0.001). Age, sex, cause of ARDS, supine $PaO_2$ and $PaO_2/FIO_2$ were not different between the respiratory responders and the nonresponders. The respiratory responders, however, showed higher mean arterial pressure than the nonresponders($91.1{\pm}13.1mmHg$ vs. $76.0{\pm}18.7mmHg$, p=0.035), and tendency of higher survival rate(9/15 vs. 2/8, p=0.074). Static compliance of the respiratory system was decreased in prone position 0.5h($28.4{\pm}7.9ml/cm$ $H_2O$ vs. $23.8{\pm}7.6ml/cm$ $H_2O$, p=0.007). The overall rate of early response(n=23) and late response(n=11) were similar(14/23 vs. 7/11, p>0.05). But patient without early response showed late response only in 25%(1/4), while patient with early response showed late response in 85.7%(6/7)(p=0.072). Five patients(22%) showed positive hemodynamic response, two of them being respiratory nonresponders. There were no differences in the baseline mean arterial pressure or the level of PEEP applied in supine between the hemodynamic responders and the hemodynamic nonresponders. Conclusions : Prone position either improved oxygenation or increased arterial pressure in significant proportion of patients with ARDS. And the respiratory response to prone position was thought to be determined in the early stage of ARDS.

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Evaluation of Artifacts by Dental Metal Prostheses and Implants on PET/CT Images: Phantom and Clinical Studies (PET/CT 영상에서의 치과재료에 의한 인공물에 관한 연구)

  • Bahn, Young-Kag;Park, Hoon-Hee;NamKoong, Hyuk;Cho, Suk-Won;Lim, Han-Sang;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.110-116
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    • 2010
  • Purpose: The X-ray attenuation coefficient based on CT images is used for attenuation correction in PET/CT. The polychromatic X-ray beam can introduce beam-hardening artifact on CT images. The aims of the study were to evaluate the effect of dental metal prostheses in phantom and patients on apparent tracer activity measured with PET/CT when using CT attenuation correction. Materials and Methods: 40 normal patients (mean age $54{\pm}12$) was scanned between Jan and Feb 2010. NEMA(National Electrical Manufactures Association) PET $Phantom^{TM}$ (NU2-1994) was filled with $^{18}F$-FDG injected into the water that insert implant and metal prostheses dental cast. Region of interest were drawn in non-artifact region, bright steak artifact region and dark streak artifact region on the same transaxial CT and PET slices. Patients and phantom with dental metal prostheses and dental implant were evaluated the change rate of CT Number and $SUV_{mean}$ in PET/CT. A paired t-test was performed to compare the ratio and the difference of the calculated values. Results: In patients with dental metal prostheses, $SUV_{mean}$ was reduced 19.64% (p<0.05) in the non-steak artifact region than the brightstreak artifact region whereas was increased 90.1% (p>0.05) in the non-steak artifact region than the dark streak artifact region. In phantom with dental metal prostheses, $SUV_{mean}$ was reduced 18.1% (p<0.05) in the non-steak artifact region than the bright streak artifact region whereas was increased 18.0% (p>0.05) in the non-steak artifact region than the dark streak artifact region. In patients with dental implant, $SUV_{mean}$ was increased 19.1% (p<0.05) in the non-steak artifact region than the bright streak artifact region whereas was increased 96.62% (p>0.05) in the non-steak artifact region than the dark streak artifact region. In phantom with dental implant, $SUV_{mean}$ was increased 14.4% (p<0.05) in the non-steak artifact region than the bright streak artifact region whereas was increased 7.0% (p>0.05) in the non-steak artifact region than the dark streak artifact region. Conclusion: When CT is used for attenuation correction in patients with dental metal prostheses, 19.1% reduced $SUV_{mean}$ is anticipated in the dark streak artifact region on CT images. The dark streak artifacts of CT by dental metal prostheses may cause false negative finding in PET/CT. We recommend that the non-attenuation corrected PET images also be evaluated for clinical use.

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